diff --git a/CHANGELOG.md b/CHANGELOG.md
index e422d7639a8..166d7cf22b7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Channels/Security: fail closed on missing provider group policy config by defaulting runtime group policy to `allowlist` (instead of inheriting `channels.defaults.groupPolicy`) when `channels.<provider>` is absent across message channels, and align runtime + security warnings/docs to the same fallback behavior (Slack, Discord, iMessage, Telegram, WhatsApp, Signal, LINE, Matrix, Mattermost, Google Chat, IRC, Nextcloud Talk, Feishu, and Zalo user flows; plus Discord message/native-command paths). (#23367) Thanks @bmendonca3.
 - CLI/Sessions: pass the configured sessions directory when resolving transcript paths in `agentCommand`, so custom `session.store` locations resume sessions reliably. Thanks @davidrudduck.
 - Gateway/Chat UI: strip inline reply/audio directive tags from non-streaming final webchat broadcasts (including `chat.inject`) while preserving empty-string message content when tags are the entire reply. (#23298) Thanks @SidQin-cyber.
 - Gateway/Restart: fix restart-loop edge cases by keeping `openclaw.mjs -> dist/entry.js` bootstrap detection explicit, reacquiring the gateway lock for in-process restart fallback paths, and tightening restart-loop regression coverage. (#23416) Thanks @jeffwnli.
diff --git a/docs/channels/discord.md b/docs/channels/discord.md
index 6cdd3aa410c..334c6d78ee5 100644
--- a/docs/channels/discord.md
+++ b/docs/channels/discord.md
@@ -425,7 +425,7 @@ Example:
 }
 ```
 
-    If you only set `DISCORD_BOT_TOKEN` and do not create a `channels.discord` block, runtime fallback is `groupPolicy="allowlist"` (with a warning in logs).
+    If you only set `DISCORD_BOT_TOKEN` and do not create a `channels.discord` block, runtime fallback is `groupPolicy="allowlist"` (with a warning in logs), even if `channels.defaults.groupPolicy` is `open`.
 
   </Tab>
 
diff --git a/docs/channels/groups.md b/docs/channels/groups.md
index 6bd278846c5..00118c546b5 100644
--- a/docs/channels/groups.md
+++ b/docs/channels/groups.md
@@ -190,6 +190,7 @@ Notes:
 - Group DMs are controlled separately (`channels.discord.dm.*`, `channels.slack.dm.*`).
 - Telegram allowlist can match user IDs (`"123456789"`, `"telegram:123456789"`, `"tg:123456789"`) or usernames (`"@alice"` or `"alice"`); prefixes are case-insensitive.
 - Default is `groupPolicy: "allowlist"`; if your group allowlist is empty, group messages are blocked.
+- Runtime safety: when a provider block is completely missing (`channels.<provider>` absent), group policy falls back to a fail-closed mode (typically `allowlist`) instead of inheriting `channels.defaults.groupPolicy`.
 
 Quick mental model (evaluation order for group messages):
 
diff --git a/docs/channels/imessage.md b/docs/channels/imessage.md
index d7a1b633597..5720da1714a 100644
--- a/docs/channels/imessage.md
+++ b/docs/channels/imessage.md
@@ -158,6 +158,7 @@ imsg send <handle> "test"
     Group sender allowlist: `channels.imessage.groupAllowFrom`.
 
     Runtime fallback: if `groupAllowFrom` is unset, iMessage group sender checks fall back to `allowFrom` when available.
+    Runtime note: if `channels.imessage` is completely missing, runtime falls back to `groupPolicy="allowlist"` and logs a warning (even if `channels.defaults.groupPolicy` is set).
 
     Mention gating for groups:
 
diff --git a/docs/channels/line.md b/docs/channels/line.md
index d32e683fbeb..b87cbd3f5fb 100644
--- a/docs/channels/line.md
+++ b/docs/channels/line.md
@@ -118,6 +118,7 @@ Allowlists and policies:
 - `channels.line.groupPolicy`: `allowlist | open | disabled`
 - `channels.line.groupAllowFrom`: allowlisted LINE user IDs for groups
 - Per-group overrides: `channels.line.groups.<groupId>.allowFrom`
+- Runtime note: if `channels.line` is completely missing, runtime falls back to `groupPolicy="allowlist"` for group checks (even if `channels.defaults.groupPolicy` is set).
 
 LINE IDs are case-sensitive. Valid IDs look like:
 
diff --git a/docs/channels/matrix.md b/docs/channels/matrix.md
index 04205d94971..9bb56d1ddb7 100644
--- a/docs/channels/matrix.md
+++ b/docs/channels/matrix.md
@@ -195,6 +195,7 @@ Notes:
 ## Rooms (groups)
 
 - Default: `channels.matrix.groupPolicy = "allowlist"` (mention-gated). Use `channels.defaults.groupPolicy` to override the default when unset.
+- Runtime note: if `channels.matrix` is completely missing, runtime falls back to `groupPolicy="allowlist"` for room checks (even if `channels.defaults.groupPolicy` is set).
 - Allowlist rooms with `channels.matrix.groups` (room IDs or aliases; names are resolved to IDs when directory search finds a single exact match):
 
 ```json5
diff --git a/docs/channels/mattermost.md b/docs/channels/mattermost.md
index fa0d9393e0f..350fa8429c4 100644
--- a/docs/channels/mattermost.md
+++ b/docs/channels/mattermost.md
@@ -103,6 +103,7 @@ Notes:
 - Default: `channels.mattermost.groupPolicy = "allowlist"` (mention-gated).
 - Allowlist senders with `channels.mattermost.groupAllowFrom` (user IDs or `@username`).
 - Open channels: `channels.mattermost.groupPolicy="open"` (mention-gated).
+- Runtime note: if `channels.mattermost` is completely missing, runtime falls back to `groupPolicy="allowlist"` for group checks (even if `channels.defaults.groupPolicy` is set).
 
 ## Targets for outbound delivery
 
diff --git a/docs/channels/signal.md b/docs/channels/signal.md
index 60bb5f7ce92..b216af120ce 100644
--- a/docs/channels/signal.md
+++ b/docs/channels/signal.md
@@ -195,6 +195,7 @@ Groups:
 
 - `channels.signal.groupPolicy = open | allowlist | disabled`.
 - `channels.signal.groupAllowFrom` controls who can trigger in groups when `allowlist` is set.
+- Runtime note: if `channels.signal` is completely missing, runtime falls back to `groupPolicy="allowlist"` for group checks (even if `channels.defaults.groupPolicy` is set).
 
 ## How it works (behavior)
 
diff --git a/docs/channels/slack.md b/docs/channels/slack.md
index 13c53b02459..4a1bda6990b 100644
--- a/docs/channels/slack.md
+++ b/docs/channels/slack.md
@@ -165,7 +165,7 @@ For actions/directory reads, user token can be preferred when configured. For wr
 
     Channel allowlist lives under `channels.slack.channels`.
 
-    Runtime note: if `channels.slack` is completely missing (env-only setup) and `channels.defaults.groupPolicy` is unset, runtime falls back to `groupPolicy="allowlist"` and logs a warning.
+    Runtime note: if `channels.slack` is completely missing (env-only setup), runtime falls back to `groupPolicy="allowlist"` and logs a warning (even if `channels.defaults.groupPolicy` is set).
 
     Name/ID resolution:
 
diff --git a/docs/channels/telegram.md b/docs/channels/telegram.md
index 3867224fc7a..138b2b255d8 100644
--- a/docs/channels/telegram.md
+++ b/docs/channels/telegram.md
@@ -148,6 +148,7 @@ curl "https://api.telegram.org/bot<bot_token>/getUpdates"
 
     `groupAllowFrom` is used for group sender filtering. If not set, Telegram falls back to `allowFrom`.
     `groupAllowFrom` entries must be numeric Telegram user IDs.
+    Runtime note: if `channels.telegram` is completely missing, runtime falls back to `groupPolicy="allowlist"` for group policy evaluation (even if `channels.defaults.groupPolicy` is set).
 
     Example: allow any member in one specific group:
 
diff --git a/docs/channels/whatsapp.md b/docs/channels/whatsapp.md
index a6fb427bdc2..d92dfda9c75 100644
--- a/docs/channels/whatsapp.md
+++ b/docs/channels/whatsapp.md
@@ -171,7 +171,7 @@ OpenClaw recommends running WhatsApp on a separate number when possible. (The ch
     - if `groupAllowFrom` is unset, runtime falls back to `allowFrom` when available
     - sender allowlists are evaluated before mention/reply activation
 
-    Note: if no `channels.whatsapp` block exists at all, runtime group-policy fallback is effectively `open`.
+    Note: if no `channels.whatsapp` block exists at all, runtime group-policy fallback is `allowlist` (with a warning log), even if `channels.defaults.groupPolicy` is set.
 
   </Tab>
 
diff --git a/extensions/discord/src/channel.ts b/extensions/discord/src/channel.ts
index 7556f14e154..9922062c4c4 100644
--- a/extensions/discord/src/channel.ts
+++ b/extensions/discord/src/channel.ts
@@ -22,6 +22,7 @@ import {
   resolveDefaultDiscordAccountId,
   resolveDiscordGroupRequireMention,
   resolveDiscordGroupToolPolicy,
+  resolveRuntimeGroupPolicy,
   setAccountEnabledInConfigSection,
   type ChannelMessageActionAdapter,
   type ChannelPlugin,
@@ -131,7 +132,13 @@ export const discordPlugin: ChannelPlugin<ResolvedDiscordAccount> = {
     collectWarnings: ({ account, cfg }) => {
       const warnings: string[] = [];
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "open";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.discord !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "open",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       const guildEntries = account.config.guilds ?? {};
       const guildsConfigured = Object.keys(guildEntries).length > 0;
       const channelAllowlistConfigured = guildsConfigured;
diff --git a/extensions/feishu/src/bot.ts b/extensions/feishu/src/bot.ts
index 14d9219193a..7922997c7d5 100644
--- a/extensions/feishu/src/bot.ts
+++ b/extensions/feishu/src/bot.ts
@@ -2,10 +2,11 @@ import type { ClawdbotConfig, RuntimeEnv } from "openclaw/plugin-sdk";
 import {
   buildAgentMediaPayload,
   buildPendingHistoryContextFromMap,
-  recordPendingHistoryEntryIfEnabled,
   clearHistoryEntriesIfEnabled,
   DEFAULT_GROUP_HISTORY_LIMIT,
   type HistoryEntry,
+  recordPendingHistoryEntryIfEnabled,
+  resolveRuntimeGroupPolicy,
 } from "openclaw/plugin-sdk";
 import { resolveFeishuAccount } from "./accounts.js";
 import { createFeishuClient } from "./client.js";
@@ -77,6 +78,7 @@ const senderNameCache = new Map<string, { name: string; expireAt: number }>();
 // Key: appId or "default", Value: timestamp of last notification
 const permissionErrorNotifiedAt = new Map<string, number>();
 const PERMISSION_ERROR_COOLDOWN_MS = 5 * 60 * 1000; // 5 minutes
+const groupPolicyFallbackWarningShown = new Set<string>();
 
 type SenderNameResult = {
   name?: string;
@@ -563,7 +565,20 @@ export async function handleFeishuMessage(params: {
   const useAccessGroups = cfg.commands?.useAccessGroups !== false;
 
   if (isGroup) {
-    const groupPolicy = feishuCfg?.groupPolicy ?? "open";
+    const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
+    const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+      providerConfigPresent: cfg.channels?.feishu !== undefined,
+      groupPolicy: feishuCfg?.groupPolicy,
+      defaultGroupPolicy,
+      configuredFallbackPolicy: "open",
+      missingProviderFallbackPolicy: "allowlist",
+    });
+    if (providerMissingFallbackApplied && !groupPolicyFallbackWarningShown.has(account.accountId)) {
+      groupPolicyFallbackWarningShown.add(account.accountId);
+      log(
+        'feishu: channels.feishu is missing; defaulting groupPolicy to "allowlist" (group messages blocked until explicitly configured).',
+      );
+    }
     const groupAllowFrom = feishuCfg?.groupAllowFrom ?? [];
     // DEBUG: log(`feishu[${account.accountId}]: groupPolicy=${groupPolicy}`);
 
diff --git a/extensions/feishu/src/channel.ts b/extensions/feishu/src/channel.ts
index 98a622cdf46..c1f29be85e5 100644
--- a/extensions/feishu/src/channel.ts
+++ b/extensions/feishu/src/channel.ts
@@ -4,6 +4,7 @@ import {
   createDefaultChannelRuntimeState,
   DEFAULT_ACCOUNT_ID,
   PAIRING_APPROVED_MESSAGE,
+  resolveRuntimeGroupPolicy,
 } from "openclaw/plugin-sdk";
 import {
   resolveFeishuAccount,
@@ -227,7 +228,13 @@ export const feishuPlugin: ChannelPlugin<ResolvedFeishuAccount> = {
       const defaultGroupPolicy = (
         cfg.channels as Record<string, { groupPolicy?: string }> | undefined
       )?.defaults?.groupPolicy;
-      const groupPolicy = feishuCfg?.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.feishu !== undefined,
+        groupPolicy: feishuCfg?.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") return [];
       return [
         `- Feishu[${account.accountId}] groups: groupPolicy="open" allows any member to trigger (mention-gated). Set channels.feishu.groupPolicy="allowlist" + channels.feishu.groupAllowFrom to restrict senders.`,
diff --git a/extensions/googlechat/src/channel.ts b/extensions/googlechat/src/channel.ts
index 8022add55ca..9cd9bd182aa 100644
--- a/extensions/googlechat/src/channel.ts
+++ b/extensions/googlechat/src/channel.ts
@@ -11,6 +11,7 @@ import {
   PAIRING_APPROVED_MESSAGE,
   resolveChannelMediaMaxBytes,
   resolveGoogleChatGroupRequireMention,
+  resolveRuntimeGroupPolicy,
   setAccountEnabledInConfigSection,
   type ChannelDock,
   type ChannelMessageActionAdapter,
@@ -199,7 +200,13 @@ export const googlechatPlugin: ChannelPlugin<ResolvedGoogleChatAccount> = {
     collectWarnings: ({ account, cfg }) => {
       const warnings: string[] = [];
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.googlechat !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy === "open") {
         warnings.push(
           `- Google Chat spaces: groupPolicy="open" allows any space to trigger (mention-gated). Set channels.googlechat.groupPolicy="allowlist" and configure channels.googlechat.groups.`,
diff --git a/extensions/googlechat/src/monitor.ts b/extensions/googlechat/src/monitor.ts
index cee54005886..8889ec8d5f5 100644
--- a/extensions/googlechat/src/monitor.ts
+++ b/extensions/googlechat/src/monitor.ts
@@ -5,6 +5,7 @@ import {
   readJsonBodyWithLimit,
   registerWebhookTarget,
   rejectNonPostWebhookRequest,
+  resolveRuntimeGroupPolicy,
   resolveSingleWebhookTargetAsync,
   resolveWebhookPath,
   resolveWebhookTargets,
@@ -67,6 +68,7 @@ function logVerbose(core: GoogleChatCoreRuntime, runtime: GoogleChatRuntimeEnv,
 }
 
 const warnedDeprecatedUsersEmailAllowFrom = new Set<string>();
+const warnedMissingProviderGroupPolicy = new Set<string>();
 function warnDeprecatedUsersEmailEntries(
   core: GoogleChatCoreRuntime,
   runtime: GoogleChatRuntimeEnv,
@@ -427,7 +429,21 @@ async function processMessageWithPipeline(params: {
   }
 
   const defaultGroupPolicy = config.channels?.defaults?.groupPolicy;
-  const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+  const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+    providerConfigPresent: config.channels?.googlechat !== undefined,
+    groupPolicy: account.config.groupPolicy,
+    defaultGroupPolicy,
+    configuredFallbackPolicy: "allowlist",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+  if (providerMissingFallbackApplied && !warnedMissingProviderGroupPolicy.has(account.accountId)) {
+    warnedMissingProviderGroupPolicy.add(account.accountId);
+    logVerbose(
+      core,
+      runtime,
+      'googlechat: channels.googlechat is missing; defaulting groupPolicy to "allowlist" (space messages blocked until explicitly configured).',
+    );
+  }
   const groupConfigResolved = resolveGroupConfig({
     groupId: spaceId,
     groupName: space.displayName ?? null,
diff --git a/extensions/imessage/src/channel.ts b/extensions/imessage/src/channel.ts
index 00696414f23..aacc3246d25 100644
--- a/extensions/imessage/src/channel.ts
+++ b/extensions/imessage/src/channel.ts
@@ -18,6 +18,7 @@ import {
   resolveIMessageAccount,
   resolveIMessageGroupRequireMention,
   resolveIMessageGroupToolPolicy,
+  resolveRuntimeGroupPolicy,
   setAccountEnabledInConfigSection,
   type ChannelPlugin,
   type ResolvedIMessageAccount,
@@ -98,7 +99,13 @@ export const imessagePlugin: ChannelPlugin<ResolvedIMessageAccount> = {
     },
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.imessage !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/irc/src/channel.ts b/extensions/irc/src/channel.ts
index 024f379c3d0..18bcece05ad 100644
--- a/extensions/irc/src/channel.ts
+++ b/extensions/irc/src/channel.ts
@@ -4,6 +4,7 @@ import {
   formatPairingApproveHint,
   getChatChannelMeta,
   PAIRING_APPROVED_MESSAGE,
+  resolveRuntimeGroupPolicy,
   setAccountEnabledInConfigSection,
   deleteAccountFromConfigSection,
   type ChannelPlugin,
@@ -135,7 +136,13 @@ export const ircPlugin: ChannelPlugin<ResolvedIrcAccount, IrcProbe> = {
     collectWarnings: ({ account, cfg }) => {
       const warnings: string[] = [];
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.irc !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy === "open") {
         warnings.push(
           '- IRC channels: groupPolicy="open" allows all channels and senders (mention-gated). Prefer channels.irc.groupPolicy="allowlist" with channels.irc.groups.',
diff --git a/extensions/irc/src/inbound.ts b/extensions/irc/src/inbound.ts
index abd523ed17c..eb6daeff611 100644
--- a/extensions/irc/src/inbound.ts
+++ b/extensions/irc/src/inbound.ts
@@ -2,6 +2,7 @@ import {
   createReplyPrefixOptions,
   logInboundDrop,
   resolveControlCommandGate,
+  resolveRuntimeGroupPolicy,
   type OpenClawConfig,
   type RuntimeEnv,
 } from "openclaw/plugin-sdk";
@@ -19,6 +20,7 @@ import { sendMessageIrc } from "./send.js";
 import type { CoreConfig, IrcInboundMessage } from "./types.js";
 
 const CHANNEL_ID = "irc" as const;
+const warnedMissingProviderGroupPolicy = new Set<string>();
 
 const escapeIrcRegexLiteral = (value: string) => value.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
 
@@ -85,7 +87,19 @@ export async function handleIrcInbound(params: {
 
   const dmPolicy = account.config.dmPolicy ?? "pairing";
   const defaultGroupPolicy = config.channels?.defaults?.groupPolicy;
-  const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+  const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+    providerConfigPresent: config.channels?.irc !== undefined,
+    groupPolicy: account.config.groupPolicy,
+    defaultGroupPolicy,
+    configuredFallbackPolicy: "allowlist",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+  if (providerMissingFallbackApplied && !warnedMissingProviderGroupPolicy.has(account.accountId)) {
+    warnedMissingProviderGroupPolicy.add(account.accountId);
+    runtime.log?.(
+      'irc: channels.irc is missing; defaulting groupPolicy to "allowlist" (channel messages blocked until explicitly configured).',
+    );
+  }
 
   const configAllowFrom = normalizeIrcAllowlist(account.config.allowFrom);
   const configGroupAllowFrom = normalizeIrcAllowlist(account.config.groupAllowFrom);
diff --git a/extensions/line/src/channel.ts b/extensions/line/src/channel.ts
index cc30264e1e1..f5c72cf81b4 100644
--- a/extensions/line/src/channel.ts
+++ b/extensions/line/src/channel.ts
@@ -3,6 +3,7 @@ import {
   DEFAULT_ACCOUNT_ID,
   LineConfigSchema,
   processLineMessage,
+  resolveRuntimeGroupPolicy,
   type ChannelPlugin,
   type ChannelStatusIssue,
   type OpenClawConfig,
@@ -163,7 +164,13 @@ export const linePlugin: ChannelPlugin<ResolvedLineAccount> = {
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = (cfg.channels?.defaults as { groupPolicy?: string } | undefined)
         ?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.line !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/matrix/src/channel.ts b/extensions/matrix/src/channel.ts
index 3cd699f252c..75e4b464660 100644
--- a/extensions/matrix/src/channel.ts
+++ b/extensions/matrix/src/channel.ts
@@ -6,6 +6,7 @@ import {
   formatPairingApproveHint,
   normalizeAccountId,
   PAIRING_APPROVED_MESSAGE,
+  resolveRuntimeGroupPolicy,
   setAccountEnabledInConfigSection,
   type ChannelPlugin,
 } from "openclaw/plugin-sdk";
@@ -170,7 +171,13 @@ export const matrixPlugin: ChannelPlugin<ResolvedMatrixAccount> = {
     },
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = (cfg as CoreConfig).channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: (cfg as CoreConfig).channels?.matrix !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/matrix/src/matrix/monitor/index.ts b/extensions/matrix/src/matrix/monitor/index.ts
index df6d87fad48..91648498936 100644
--- a/extensions/matrix/src/matrix/monitor/index.ts
+++ b/extensions/matrix/src/matrix/monitor/index.ts
@@ -1,5 +1,10 @@
 import { format } from "node:util";
-import { mergeAllowlist, summarizeMapping, type RuntimeEnv } from "openclaw/plugin-sdk";
+import {
+  mergeAllowlist,
+  resolveRuntimeGroupPolicy,
+  summarizeMapping,
+  type RuntimeEnv,
+} from "openclaw/plugin-sdk";
 import { resolveMatrixTargets } from "../../resolve-targets.js";
 import { getMatrixRuntime } from "../../runtime.js";
 import type { CoreConfig, ReplyToMode } from "../../types.js";
@@ -243,7 +248,20 @@ export async function monitorMatrixProvider(opts: MonitorMatrixOpts = {}): Promi
 
   const mentionRegexes = core.channel.mentions.buildMentionRegexes(cfg);
   const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-  const groupPolicyRaw = accountConfig.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+  const { groupPolicy: groupPolicyRaw, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy(
+    {
+      providerConfigPresent: cfg.channels?.matrix !== undefined,
+      groupPolicy: accountConfig.groupPolicy,
+      defaultGroupPolicy,
+      configuredFallbackPolicy: "allowlist",
+      missingProviderFallbackPolicy: "allowlist",
+    },
+  );
+  if (providerMissingFallbackApplied) {
+    logVerboseMessage(
+      'matrix: channels.matrix is missing; defaulting groupPolicy to "allowlist" (room messages blocked until explicitly configured).',
+    );
+  }
   const groupPolicy = allowlistOnly && groupPolicyRaw === "open" ? "allowlist" : groupPolicyRaw;
   const replyToMode = opts.replyToMode ?? accountConfig.replyToMode ?? "off";
   const threadReplies = accountConfig.threadReplies ?? "inbound";
diff --git a/extensions/mattermost/src/channel.ts b/extensions/mattermost/src/channel.ts
index 3935d5f205e..55e189b55de 100644
--- a/extensions/mattermost/src/channel.ts
+++ b/extensions/mattermost/src/channel.ts
@@ -6,6 +6,7 @@ import {
   formatPairingApproveHint,
   migrateBaseNameToDefaultAccount,
   normalizeAccountId,
+  resolveRuntimeGroupPolicy,
   setAccountEnabledInConfigSection,
   type ChannelMessageActionAdapter,
   type ChannelMessageActionName,
@@ -229,7 +230,13 @@ export const mattermostPlugin: ChannelPlugin<ResolvedMattermostAccount> = {
     },
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.mattermost !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/mattermost/src/mattermost/monitor.ts b/extensions/mattermost/src/mattermost/monitor.ts
index b2c921b155d..81777f213e4 100644
--- a/extensions/mattermost/src/mattermost/monitor.ts
+++ b/extensions/mattermost/src/mattermost/monitor.ts
@@ -16,6 +16,7 @@ import {
   DEFAULT_GROUP_HISTORY_LIMIT,
   recordPendingHistoryEntryIfEnabled,
   resolveControlCommandGate,
+  resolveRuntimeGroupPolicy,
   resolveChannelMediaMaxBytes,
   type HistoryEntry,
 } from "openclaw/plugin-sdk";
@@ -242,6 +243,19 @@ export async function monitorMattermostProvider(opts: MonitorMattermostOpts = {}
     cfg.messages?.groupChat?.historyLimit ?? DEFAULT_GROUP_HISTORY_LIMIT,
   );
   const channelHistories = new Map<string, HistoryEntry[]>();
+  const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
+  const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+    providerConfigPresent: cfg.channels?.mattermost !== undefined,
+    groupPolicy: account.config.groupPolicy,
+    defaultGroupPolicy,
+    configuredFallbackPolicy: "allowlist",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+  if (providerMissingFallbackApplied) {
+    logVerboseMessage(
+      'mattermost: channels.mattermost is missing; defaulting groupPolicy to "allowlist" (group messages blocked until explicitly configured).',
+    );
+  }
 
   const fetchWithAuth: FetchLike = (input, init) => {
     const headers = new Headers(init?.headers);
@@ -375,8 +389,6 @@ export async function monitorMattermostProvider(opts: MonitorMattermostOpts = {}
       senderId;
     const rawText = post.message?.trim() || "";
     const dmPolicy = account.config.dmPolicy ?? "pairing";
-    const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-    const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
     const configAllowFrom = normalizeAllowList(account.config.allowFrom ?? []);
     const configGroupAllowFrom = normalizeAllowList(account.config.groupAllowFrom ?? []);
     const storeAllowFrom = normalizeAllowList(
@@ -887,8 +899,6 @@ export async function monitorMattermostProvider(opts: MonitorMattermostOpts = {}
         }
       }
     } else if (kind) {
-      const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
       if (groupPolicy === "disabled") {
         logVerboseMessage(`mattermost: drop reaction (groupPolicy=disabled channel=${channelId})`);
         return;
diff --git a/extensions/msteams/src/channel.ts b/extensions/msteams/src/channel.ts
index d7e9b3088e8..9e35450d77a 100644
--- a/extensions/msteams/src/channel.ts
+++ b/extensions/msteams/src/channel.ts
@@ -6,6 +6,7 @@ import {
   DEFAULT_ACCOUNT_ID,
   MSTeamsConfigSchema,
   PAIRING_APPROVED_MESSAGE,
+  resolveRuntimeGroupPolicy,
 } from "openclaw/plugin-sdk";
 import { listMSTeamsDirectoryGroupsLive, listMSTeamsDirectoryPeersLive } from "./directory-live.js";
 import { msteamsOnboardingAdapter } from "./onboarding.js";
@@ -128,7 +129,13 @@ export const msteamsPlugin: ChannelPlugin<ResolvedMSTeamsAccount> = {
   security: {
     collectWarnings: ({ cfg }) => {
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = cfg.channels?.msteams?.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.msteams !== undefined,
+        groupPolicy: cfg.channels?.msteams?.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/nextcloud-talk/src/channel.ts b/extensions/nextcloud-talk/src/channel.ts
index 7471d70dab0..3b7769013f8 100644
--- a/extensions/nextcloud-talk/src/channel.ts
+++ b/extensions/nextcloud-talk/src/channel.ts
@@ -5,6 +5,7 @@ import {
   deleteAccountFromConfigSection,
   formatPairingApproveHint,
   normalizeAccountId,
+  resolveRuntimeGroupPolicy,
   setAccountEnabledInConfigSection,
   type ChannelPlugin,
   type OpenClawConfig,
@@ -129,7 +130,14 @@ export const nextcloudTalkPlugin: ChannelPlugin<ResolvedNextcloudTalkAccount> =
     },
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent:
+          (cfg.channels as Record<string, unknown> | undefined)?.["nextcloud-talk"] !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/nextcloud-talk/src/inbound.ts b/extensions/nextcloud-talk/src/inbound.ts
index 642e010b06d..149bff15818 100644
--- a/extensions/nextcloud-talk/src/inbound.ts
+++ b/extensions/nextcloud-talk/src/inbound.ts
@@ -2,6 +2,7 @@ import {
   createReplyPrefixOptions,
   logInboundDrop,
   resolveControlCommandGate,
+  resolveRuntimeGroupPolicy,
   type OpenClawConfig,
   type RuntimeEnv,
 } from "openclaw/plugin-sdk";
@@ -20,6 +21,7 @@ import { sendMessageNextcloudTalk } from "./send.js";
 import type { CoreConfig, GroupPolicy, NextcloudTalkInboundMessage } from "./types.js";
 
 const CHANNEL_ID = "nextcloud-talk" as const;
+const warnedMissingProviderGroupPolicy = new Set<string>();
 
 async function deliverNextcloudTalkReply(params: {
   payload: { text?: string; mediaUrls?: string[]; mediaUrl?: string; replyToId?: string };
@@ -84,12 +86,26 @@ export async function handleNextcloudTalkInbound(params: {
   statusSink?.({ lastInboundAt: message.timestamp });
 
   const dmPolicy = account.config.dmPolicy ?? "pairing";
-  const defaultGroupPolicy = (config.channels as Record<string, unknown> | undefined)?.defaults as
-    | { groupPolicy?: string }
-    | undefined;
-  const groupPolicy = (account.config.groupPolicy ??
-    defaultGroupPolicy?.groupPolicy ??
-    "allowlist") as GroupPolicy;
+  const defaultGroupPolicy = (
+    (config.channels as Record<string, unknown> | undefined)?.defaults as
+      | { groupPolicy?: string }
+      | undefined
+  )?.groupPolicy as GroupPolicy | undefined;
+  const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+    providerConfigPresent:
+      ((config.channels as Record<string, unknown> | undefined)?.["nextcloud-talk"] ??
+        undefined) !== undefined,
+    groupPolicy: account.config.groupPolicy as GroupPolicy | undefined,
+    defaultGroupPolicy,
+    configuredFallbackPolicy: "allowlist",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+  if (providerMissingFallbackApplied && !warnedMissingProviderGroupPolicy.has(account.accountId)) {
+    warnedMissingProviderGroupPolicy.add(account.accountId);
+    runtime.log?.(
+      'nextcloud-talk: channels.nextcloud-talk is missing; defaulting groupPolicy to "allowlist" (room messages blocked until explicitly configured).',
+    );
+  }
 
   const configAllowFrom = normalizeNextcloudTalkAllowlist(account.config.allowFrom);
   const configGroupAllowFrom = normalizeNextcloudTalkAllowlist(account.config.groupAllowFrom);
diff --git a/extensions/signal/src/channel.ts b/extensions/signal/src/channel.ts
index 2d627eeb9a6..db309b5a09d 100644
--- a/extensions/signal/src/channel.ts
+++ b/extensions/signal/src/channel.ts
@@ -17,6 +17,7 @@ import {
   PAIRING_APPROVED_MESSAGE,
   resolveChannelMediaMaxBytes,
   resolveDefaultSignalAccountId,
+  resolveRuntimeGroupPolicy,
   resolveSignalAccount,
   setAccountEnabledInConfigSection,
   signalOnboardingAdapter,
@@ -124,7 +125,13 @@ export const signalPlugin: ChannelPlugin<ResolvedSignalAccount> = {
     },
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.signal !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/slack/src/channel.ts b/extensions/slack/src/channel.ts
index 891dd6a590c..8eda437cfed 100644
--- a/extensions/slack/src/channel.ts
+++ b/extensions/slack/src/channel.ts
@@ -19,6 +19,7 @@ import {
   resolveDefaultSlackAccountId,
   resolveSlackAccount,
   resolveSlackReplyToMode,
+  resolveRuntimeGroupPolicy,
   resolveSlackGroupRequireMention,
   resolveSlackGroupToolPolicy,
   buildSlackThreadingToolContext,
@@ -151,7 +152,13 @@ export const slackPlugin: ChannelPlugin<ResolvedSlackAccount> = {
     collectWarnings: ({ account, cfg }) => {
       const warnings: string[] = [];
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "open";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.slack !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "open",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       const channelAllowlistConfigured =
         Boolean(account.config.channels) && Object.keys(account.config.channels ?? {}).length > 0;
 
diff --git a/extensions/telegram/src/channel.ts b/extensions/telegram/src/channel.ts
index a26dd956a6a..858e6405e55 100644
--- a/extensions/telegram/src/channel.ts
+++ b/extensions/telegram/src/channel.ts
@@ -17,6 +17,7 @@ import {
   parseTelegramReplyToMessageId,
   parseTelegramThreadId,
   resolveDefaultTelegramAccountId,
+  resolveRuntimeGroupPolicy,
   resolveTelegramAccount,
   resolveTelegramGroupRequireMention,
   resolveTelegramGroupToolPolicy,
@@ -196,7 +197,13 @@ export const telegramPlugin: ChannelPlugin<ResolvedTelegramAccount, TelegramProb
     },
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.telegram !== undefined,
+        groupPolicy: account.config.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/whatsapp/src/channel.ts b/extensions/whatsapp/src/channel.ts
index d19359630b1..8796dcc14b6 100644
--- a/extensions/whatsapp/src/channel.ts
+++ b/extensions/whatsapp/src/channel.ts
@@ -19,6 +19,7 @@ import {
   readStringParam,
   resolveDefaultWhatsAppAccountId,
   resolveWhatsAppOutboundTarget,
+  resolveRuntimeGroupPolicy,
   resolveWhatsAppAccount,
   resolveWhatsAppGroupRequireMention,
   resolveWhatsAppGroupToolPolicy,
@@ -143,7 +144,13 @@ export const whatsappPlugin: ChannelPlugin<ResolvedWhatsAppAccount> = {
     },
     collectWarnings: ({ account, cfg }) => {
       const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-      const groupPolicy = account.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+      const { groupPolicy } = resolveRuntimeGroupPolicy({
+        providerConfigPresent: cfg.channels?.whatsapp !== undefined,
+        groupPolicy: account.groupPolicy,
+        defaultGroupPolicy,
+        configuredFallbackPolicy: "allowlist",
+        missingProviderFallbackPolicy: "allowlist",
+      });
       if (groupPolicy !== "open") {
         return [];
       }
diff --git a/extensions/zalouser/src/monitor.ts b/extensions/zalouser/src/monitor.ts
index c55a76a147d..6d723e0513b 100644
--- a/extensions/zalouser/src/monitor.ts
+++ b/extensions/zalouser/src/monitor.ts
@@ -3,6 +3,7 @@ import type { OpenClawConfig, MarkdownTableMode, RuntimeEnv } from "openclaw/plu
 import {
   createReplyPrefixOptions,
   mergeAllowlist,
+  resolveRuntimeGroupPolicy,
   resolveSenderCommandAuthorization,
   summarizeMapping,
 } from "openclaw/plugin-sdk";
@@ -178,7 +179,20 @@ async function processMessage(
   const chatId = threadId;
 
   const defaultGroupPolicy = config.channels?.defaults?.groupPolicy;
-  const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "open";
+  const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+    providerConfigPresent: config.channels?.zalouser !== undefined,
+    groupPolicy: account.config.groupPolicy,
+    defaultGroupPolicy,
+    configuredFallbackPolicy: "open",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+  if (providerMissingFallbackApplied) {
+    logVerbose(
+      core,
+      runtime,
+      'zalouser: channels.zalouser is missing; defaulting groupPolicy to "allowlist" (group messages blocked until explicitly configured).',
+    );
+  }
   const groups = account.config.groups ?? {};
   if (isGroup) {
     if (groupPolicy === "disabled") {
diff --git a/extensions/zalouser/src/onboarding.ts b/extensions/zalouser/src/onboarding.ts
index 03750e1101e..23df4ce42de 100644
--- a/extensions/zalouser/src/onboarding.ts
+++ b/extensions/zalouser/src/onboarding.ts
@@ -447,7 +447,7 @@ export const zalouserOnboardingAdapter: ChannelOnboardingAdapter = {
     const accessConfig = await promptChannelAccessConfig({
       prompter,
       label: "Zalo groups",
-      currentPolicy: account.config.groupPolicy ?? "open",
+      currentPolicy: account.config.groupPolicy ?? "allowlist",
       currentEntries: Object.keys(account.config.groups ?? {}),
       placeholder: "Family, Work, 123456789",
       updatePrompt: Boolean(account.config.groups),
diff --git a/src/discord/monitor/message-handler.ts b/src/discord/monitor/message-handler.ts
index aceae950d70..8beae2e6277 100644
--- a/src/discord/monitor/message-handler.ts
+++ b/src/discord/monitor/message-handler.ts
@@ -4,6 +4,7 @@ import {
   createInboundDebouncer,
   resolveInboundDebounceMs,
 } from "../../auto-reply/inbound-debounce.js";
+import { resolveRuntimeGroupPolicy } from "../../config/runtime-group-policy.js";
 import { danger } from "../../globals.js";
 import type { DiscordMessageEvent, DiscordMessageHandler } from "./listeners.js";
 import { preflightDiscordMessage } from "./message-handler.preflight.js";
@@ -23,7 +24,13 @@ type DiscordMessageHandlerParams = Omit<
 export function createDiscordMessageHandler(
   params: DiscordMessageHandlerParams,
 ): DiscordMessageHandler {
-  const groupPolicy = params.discordConfig?.groupPolicy ?? "open";
+  const { groupPolicy } = resolveRuntimeGroupPolicy({
+    providerConfigPresent: params.cfg.channels?.discord !== undefined,
+    groupPolicy: params.discordConfig?.groupPolicy,
+    defaultGroupPolicy: params.cfg.channels?.defaults?.groupPolicy,
+    configuredFallbackPolicy: "open",
+    missingProviderFallbackPolicy: "allowlist",
+  });
   const ackReactionScope = params.cfg.messages?.ackReactionScope ?? "group-mentions";
   const debounceMs = resolveInboundDebounceMs({ cfg: params.cfg, channel: "discord" });
 
diff --git a/src/discord/monitor/native-command.ts b/src/discord/monitor/native-command.ts
index cc45838c3c9..9ab2c5c3a4c 100644
--- a/src/discord/monitor/native-command.ts
+++ b/src/discord/monitor/native-command.ts
@@ -39,6 +39,7 @@ import type { ReplyPayload } from "../../auto-reply/types.js";
 import { resolveCommandAuthorizedFromAuthorizers } from "../../channels/command-gating.js";
 import { createReplyPrefixOptions } from "../../channels/reply-prefix.js";
 import type { OpenClawConfig, loadConfig } from "../../config/config.js";
+import { resolveRuntimeGroupPolicy } from "../../config/runtime-group-policy.js";
 import { loadSessionStore, resolveStorePath } from "../../config/sessions.js";
 import { logVerbose } from "../../globals.js";
 import { createSubsystemLogger } from "../../logging/subsystem.js";
@@ -1329,8 +1330,15 @@ async function dispatchDiscordCommandInteraction(params: {
     const channelAllowlistConfigured =
       Boolean(guildInfo?.channels) && Object.keys(guildInfo?.channels ?? {}).length > 0;
     const channelAllowed = channelConfig?.allowed !== false;
+    const { groupPolicy } = resolveRuntimeGroupPolicy({
+      providerConfigPresent: cfg.channels?.discord !== undefined,
+      groupPolicy: discordConfig?.groupPolicy,
+      defaultGroupPolicy: cfg.channels?.defaults?.groupPolicy,
+      configuredFallbackPolicy: "open",
+      missingProviderFallbackPolicy: "allowlist",
+    });
     const allowByPolicy = isDiscordGroupAllowedByPolicy({
-      groupPolicy: discordConfig?.groupPolicy ?? "open",
+      groupPolicy,
       guildAllowlisted: Boolean(guildInfo),
       channelAllowlistConfigured,
       channelAllowed,
diff --git a/src/discord/monitor/provider.group-policy.test.ts b/src/discord/monitor/provider.group-policy.test.ts
index 50a3377f806..48d4f67614a 100644
--- a/src/discord/monitor/provider.group-policy.test.ts
+++ b/src/discord/monitor/provider.group-policy.test.ts
@@ -26,4 +26,13 @@ describe("resolveDiscordRuntimeGroupPolicy", () => {
     expect(resolved.groupPolicy).toBe("disabled");
     expect(resolved.providerMissingFallbackApplied).toBe(false);
   });
+
+  it("ignores explicit global defaults when provider config is missing", () => {
+    const resolved = __testing.resolveDiscordRuntimeGroupPolicy({
+      providerConfigPresent: false,
+      defaultGroupPolicy: "open",
+    });
+    expect(resolved.groupPolicy).toBe("allowlist");
+    expect(resolved.providerMissingFallbackApplied).toBe(true);
+  });
 });
diff --git a/src/discord/monitor/provider.ts b/src/discord/monitor/provider.ts
index bfe8880098d..cea9303f0da 100644
--- a/src/discord/monitor/provider.ts
+++ b/src/discord/monitor/provider.ts
@@ -21,6 +21,7 @@ import {
 } from "../../config/commands.js";
 import type { OpenClawConfig, ReplyToMode } from "../../config/config.js";
 import { loadConfig } from "../../config/config.js";
+import { resolveRuntimeGroupPolicy } from "../../config/runtime-group-policy.js";
 import type { GroupPolicy } from "../../config/types.base.js";
 import { danger, logVerbose, shouldLogVerbose, warn } from "../../globals.js";
 import { formatErrorMessage } from "../../infra/errors.js";
@@ -179,15 +180,13 @@ function resolveDiscordRuntimeGroupPolicy(params: {
   groupPolicy: GroupPolicy;
   providerMissingFallbackApplied: boolean;
 } {
-  const groupPolicy =
-    params.groupPolicy ??
-    params.defaultGroupPolicy ??
-    (params.providerConfigPresent ? "open" : "allowlist");
-  const providerMissingFallbackApplied =
-    !params.providerConfigPresent &&
-    params.groupPolicy === undefined &&
-    params.defaultGroupPolicy === undefined;
-  return { groupPolicy, providerMissingFallbackApplied };
+  return resolveRuntimeGroupPolicy({
+    providerConfigPresent: params.providerConfigPresent,
+    groupPolicy: params.groupPolicy,
+    defaultGroupPolicy: params.defaultGroupPolicy,
+    configuredFallbackPolicy: "open",
+    missingProviderFallbackPolicy: "allowlist",
+  });
 }
 
 async function deployDiscordCommands(params: {
@@ -265,20 +264,22 @@ export async function monitorDiscordProvider(opts: MonitorDiscordOpts = {}) {
 
   const runtime: RuntimeEnv = opts.runtime ?? createNonExitingRuntime();
 
-  const discordCfg = account.config;
+  const rawDiscordCfg = account.config;
   const discordRootThreadBindings = cfg.channels?.discord?.threadBindings;
   const discordAccountThreadBindings =
     cfg.channels?.discord?.accounts?.[account.accountId]?.threadBindings;
-  const discordRestFetch = resolveDiscordRestFetch(discordCfg.proxy, runtime);
-  const dmConfig = discordCfg.dm;
-  let guildEntries = discordCfg.guilds;
+  const discordRestFetch = resolveDiscordRestFetch(rawDiscordCfg.proxy, runtime);
+  const dmConfig = rawDiscordCfg.dm;
+  let guildEntries = rawDiscordCfg.guilds;
   const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
   const providerConfigPresent = cfg.channels?.discord !== undefined;
   const { groupPolicy, providerMissingFallbackApplied } = resolveDiscordRuntimeGroupPolicy({
     providerConfigPresent,
-    groupPolicy: discordCfg.groupPolicy,
+    groupPolicy: rawDiscordCfg.groupPolicy,
     defaultGroupPolicy,
   });
+  const discordCfg =
+    rawDiscordCfg.groupPolicy === groupPolicy ? rawDiscordCfg : { ...rawDiscordCfg, groupPolicy };
   if (providerMissingFallbackApplied) {
     runtime.log?.(
       warn(
diff --git a/src/imessage/monitor/monitor-provider.ts b/src/imessage/monitor/monitor-provider.ts
index 375ada6ac4b..2a114e8465e 100644
--- a/src/imessage/monitor/monitor-provider.ts
+++ b/src/imessage/monitor/monitor-provider.ts
@@ -16,8 +16,10 @@ import { createReplyDispatcher } from "../../auto-reply/reply/reply-dispatcher.j
 import { createReplyPrefixOptions } from "../../channels/reply-prefix.js";
 import { recordInboundSession } from "../../channels/session.js";
 import { loadConfig } from "../../config/config.js";
+import { resolveRuntimeGroupPolicy } from "../../config/runtime-group-policy.js";
 import { readSessionUpdatedAt, resolveStorePath } from "../../config/sessions.js";
-import { danger, logVerbose, shouldLogVerbose } from "../../globals.js";
+import type { GroupPolicy } from "../../config/types.base.js";
+import { danger, logVerbose, shouldLogVerbose, warn } from "../../globals.js";
 import { normalizeScpRemoteHost } from "../../infra/scp-host.js";
 import { waitForTransportReady } from "../../infra/transport-ready.js";
 import { mediaKindFromMime } from "../../media/constants.js";
@@ -120,6 +122,23 @@ class SentMessageCache {
   }
 }
 
+function resolveIMessageRuntimeGroupPolicy(params: {
+  providerConfigPresent: boolean;
+  groupPolicy?: GroupPolicy;
+  defaultGroupPolicy?: GroupPolicy;
+}): {
+  groupPolicy: GroupPolicy;
+  providerMissingFallbackApplied: boolean;
+} {
+  return resolveRuntimeGroupPolicy({
+    providerConfigPresent: params.providerConfigPresent,
+    groupPolicy: params.groupPolicy,
+    defaultGroupPolicy: params.defaultGroupPolicy,
+    configuredFallbackPolicy: "open",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+}
+
 export async function monitorIMessageProvider(opts: MonitorIMessageOpts = {}): Promise<void> {
   const runtime = resolveRuntime(opts);
   const cfg = opts.config ?? loadConfig();
@@ -144,7 +163,18 @@ export async function monitorIMessageProvider(opts: MonitorIMessageOpts = {}): P
       (imessageCfg.allowFrom && imessageCfg.allowFrom.length > 0 ? imessageCfg.allowFrom : []),
   );
   const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-  const groupPolicy = imessageCfg.groupPolicy ?? defaultGroupPolicy ?? "open";
+  const { groupPolicy, providerMissingFallbackApplied } = resolveIMessageRuntimeGroupPolicy({
+    providerConfigPresent: cfg.channels?.imessage !== undefined,
+    groupPolicy: imessageCfg.groupPolicy,
+    defaultGroupPolicy,
+  });
+  if (providerMissingFallbackApplied) {
+    runtime.log?.(
+      warn(
+        'imessage: channels.imessage is missing; defaulting groupPolicy to "allowlist" (group messages blocked until explicitly configured).',
+      ),
+    );
+  }
   const dmPolicy = imessageCfg.dmPolicy ?? "pairing";
   const includeAttachments = opts.includeAttachments ?? imessageCfg.includeAttachments ?? false;
   const mediaMaxBytes = (opts.mediaMaxMb ?? imessageCfg.mediaMaxMb ?? 16) * 1024 * 1024;
@@ -508,3 +538,7 @@ export async function monitorIMessageProvider(opts: MonitorIMessageOpts = {}): P
     await client.stop();
   }
 }
+
+export const __testing = {
+  resolveIMessageRuntimeGroupPolicy,
+};
diff --git a/src/line/bot-handlers.ts b/src/line/bot-handlers.ts
index 206a4d185cb..096d7fcc188 100644
--- a/src/line/bot-handlers.ts
+++ b/src/line/bot-handlers.ts
@@ -8,6 +8,7 @@ import type {
   PostbackEvent,
 } from "@line/bot-sdk";
 import type { OpenClawConfig } from "../config/config.js";
+import { resolveRuntimeGroupPolicy } from "../config/runtime-group-policy.js";
 import { danger, logVerbose } from "../globals.js";
 import { resolvePairingIdLabel } from "../pairing/pairing-labels.js";
 import { buildPairingReply } from "../pairing/pairing-messages.js";
@@ -40,6 +41,8 @@ export interface LineHandlerContext {
   processMessage: (ctx: LineInboundContext) => Promise<void>;
 }
 
+let lineGroupPolicyFallbackWarned = false;
+
 function resolveLineGroupConfig(params: {
   config: ResolvedLineAccount["config"];
   groupId?: string;
@@ -133,7 +136,19 @@ async function shouldProcessLineEvent(
     dmPolicy,
   });
   const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-  const groupPolicy = account.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+  const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+    providerConfigPresent: cfg.channels?.line !== undefined,
+    groupPolicy: account.config.groupPolicy,
+    defaultGroupPolicy,
+    configuredFallbackPolicy: "allowlist",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+  if (providerMissingFallbackApplied && !lineGroupPolicyFallbackWarned) {
+    lineGroupPolicyFallbackWarned = true;
+    logVerbose(
+      'line: channels.line is missing; defaulting groupPolicy to "allowlist" (group messages blocked until explicitly configured).',
+    );
+  }
 
   if (isGroup) {
     if (groupConfig?.enabled === false) {
diff --git a/src/plugin-sdk/index.ts b/src/plugin-sdk/index.ts
index a3f58c034cc..07e3c63d7f6 100644
--- a/src/plugin-sdk/index.ts
+++ b/src/plugin-sdk/index.ts
@@ -132,6 +132,10 @@ export type {
   MSTeamsReplyStyle,
   MSTeamsTeamConfig,
 } from "../config/types.js";
+export {
+  resolveRuntimeGroupPolicy,
+  type RuntimeGroupPolicyResolution,
+} from "../config/runtime-group-policy.js";
 export {
   DiscordConfigSchema,
   GoogleChatConfigSchema,
diff --git a/src/signal/monitor.ts b/src/signal/monitor.ts
index 0d4d72ee58e..c9bc8dcb219 100644
--- a/src/signal/monitor.ts
+++ b/src/signal/monitor.ts
@@ -3,6 +3,7 @@ import { DEFAULT_GROUP_HISTORY_LIMIT, type HistoryEntry } from "../auto-reply/re
 import type { ReplyPayload } from "../auto-reply/types.js";
 import type { OpenClawConfig } from "../config/config.js";
 import { loadConfig } from "../config/config.js";
+import { resolveRuntimeGroupPolicy } from "../config/runtime-group-policy.js";
 import type { SignalReactionNotificationMode } from "../config/types.js";
 import { waitForTransportReady } from "../infra/transport-ready.js";
 import { saveMediaBuffer } from "../media/store.js";
@@ -345,7 +346,18 @@ export async function monitorSignalProvider(opts: MonitorSignalOpts = {}): Promi
         : []),
   );
   const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-  const groupPolicy = accountInfo.config.groupPolicy ?? defaultGroupPolicy ?? "allowlist";
+  const { groupPolicy, providerMissingFallbackApplied } = resolveRuntimeGroupPolicy({
+    providerConfigPresent: cfg.channels?.signal !== undefined,
+    groupPolicy: accountInfo.config.groupPolicy,
+    defaultGroupPolicy,
+    configuredFallbackPolicy: "allowlist",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+  if (providerMissingFallbackApplied) {
+    runtime.log?.(
+      'signal: channels.signal is missing; defaulting groupPolicy to "allowlist" (group messages blocked until explicitly configured).',
+    );
+  }
   const reactionMode = accountInfo.config.reactionNotifications ?? "own";
   const reactionAllowlist = normalizeAllowList(accountInfo.config.reactionAllowlist);
   const mediaMaxBytes = (opts.mediaMaxMb ?? accountInfo.config.mediaMaxMb ?? 8) * 1024 * 1024;
diff --git a/src/slack/monitor/provider.group-policy.test.ts b/src/slack/monitor/provider.group-policy.test.ts
index 43bc8dfec54..29478d13e7a 100644
--- a/src/slack/monitor/provider.group-policy.test.ts
+++ b/src/slack/monitor/provider.group-policy.test.ts
@@ -18,12 +18,12 @@ describe("resolveSlackRuntimeGroupPolicy", () => {
     expect(resolved.providerMissingFallbackApplied).toBe(false);
   });
 
-  it("respects explicit global defaults", () => {
+  it("ignores explicit global defaults when provider config is missing", () => {
     const resolved = __testing.resolveSlackRuntimeGroupPolicy({
       providerConfigPresent: false,
       defaultGroupPolicy: "open",
     });
-    expect(resolved.groupPolicy).toBe("open");
-    expect(resolved.providerMissingFallbackApplied).toBe(false);
+    expect(resolved.groupPolicy).toBe("allowlist");
+    expect(resolved.providerMissingFallbackApplied).toBe(true);
   });
 });
diff --git a/src/slack/monitor/provider.ts b/src/slack/monitor/provider.ts
index 4d9d50331a9..1d52d561036 100644
--- a/src/slack/monitor/provider.ts
+++ b/src/slack/monitor/provider.ts
@@ -10,6 +10,7 @@ import {
   summarizeMapping,
 } from "../../channels/allowlists/resolve-utils.js";
 import { loadConfig } from "../../config/config.js";
+import { resolveRuntimeGroupPolicy } from "../../config/runtime-group-policy.js";
 import type { SessionScope } from "../../config/sessions.js";
 import type { GroupPolicy } from "../../config/types.base.js";
 import { warn } from "../../globals.js";
@@ -50,15 +51,13 @@ function resolveSlackRuntimeGroupPolicy(params: {
   groupPolicy: GroupPolicy;
   providerMissingFallbackApplied: boolean;
 } {
-  const groupPolicy =
-    params.groupPolicy ??
-    params.defaultGroupPolicy ??
-    (params.providerConfigPresent ? "open" : "allowlist");
-  const providerMissingFallbackApplied =
-    !params.providerConfigPresent &&
-    params.groupPolicy === undefined &&
-    params.defaultGroupPolicy === undefined;
-  return { groupPolicy, providerMissingFallbackApplied };
+  return resolveRuntimeGroupPolicy({
+    providerConfigPresent: params.providerConfigPresent,
+    groupPolicy: params.groupPolicy,
+    defaultGroupPolicy: params.defaultGroupPolicy,
+    configuredFallbackPolicy: "open",
+    missingProviderFallbackPolicy: "allowlist",
+  });
 }
 
 function parseApiAppIdFromAppToken(raw?: string) {
diff --git a/src/telegram/group-access.ts b/src/telegram/group-access.ts
index 02375218171..571457d3b65 100644
--- a/src/telegram/group-access.ts
+++ b/src/telegram/group-access.ts
@@ -1,5 +1,6 @@
 import type { OpenClawConfig } from "../config/config.js";
 import type { ChannelGroupPolicy } from "../config/group-policy.js";
+import { resolveRuntimeGroupPolicy } from "../config/runtime-group-policy.js";
 import type {
   TelegramAccountConfig,
   TelegramGroupConfig,
@@ -72,6 +73,19 @@ export type TelegramGroupPolicyAccessResult =
       groupPolicy: "open" | "disabled" | "allowlist";
     };
 
+export const resolveTelegramRuntimeGroupPolicy = (params: {
+  providerConfigPresent: boolean;
+  groupPolicy?: TelegramAccountConfig["groupPolicy"];
+  defaultGroupPolicy?: TelegramAccountConfig["groupPolicy"];
+}) =>
+  resolveRuntimeGroupPolicy({
+    providerConfigPresent: params.providerConfigPresent,
+    groupPolicy: params.groupPolicy,
+    defaultGroupPolicy: params.defaultGroupPolicy,
+    configuredFallbackPolicy: "open",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+
 export const evaluateTelegramGroupPolicyAccess = (params: {
   isGroup: boolean;
   chatId: string | number;
@@ -90,20 +104,21 @@ export const evaluateTelegramGroupPolicyAccess = (params: {
   requireSenderForAllowlistAuthorization: boolean;
   checkChatAllowlist: boolean;
 }): TelegramGroupPolicyAccessResult => {
+  const { groupPolicy: runtimeFallbackPolicy } = resolveTelegramRuntimeGroupPolicy({
+    providerConfigPresent: params.cfg.channels?.telegram !== undefined,
+    groupPolicy: params.telegramCfg.groupPolicy,
+    defaultGroupPolicy: params.cfg.channels?.defaults?.groupPolicy,
+  });
   const fallbackPolicy =
-    firstDefined(
-      params.telegramCfg.groupPolicy,
-      params.cfg.channels?.defaults?.groupPolicy,
-      "open",
-    ) ?? "open";
+    firstDefined(params.telegramCfg.groupPolicy, params.cfg.channels?.defaults?.groupPolicy) ??
+    runtimeFallbackPolicy;
   const groupPolicy = params.useTopicAndGroupOverrides
     ? (firstDefined(
         params.topicConfig?.groupPolicy,
         params.groupConfig?.groupPolicy,
         params.telegramCfg.groupPolicy,
         params.cfg.channels?.defaults?.groupPolicy,
-        "open",
-      ) ?? "open")
+      ) ?? runtimeFallbackPolicy)
     : fallbackPolicy;
 
   if (!params.isGroup || !params.enforcePolicy) {
diff --git a/src/web/inbound/access-control.ts b/src/web/inbound/access-control.ts
index a7c2601e2b3..5f5737f3a2b 100644
--- a/src/web/inbound/access-control.ts
+++ b/src/web/inbound/access-control.ts
@@ -1,4 +1,5 @@
 import { loadConfig } from "../../config/config.js";
+import { resolveRuntimeGroupPolicy } from "../../config/runtime-group-policy.js";
 import { logVerbose } from "../../globals.js";
 import { buildPairingReply } from "../../pairing/pairing-messages.js";
 import {
@@ -17,6 +18,23 @@ export type InboundAccessControlResult = {
 
 const PAIRING_REPLY_HISTORY_GRACE_MS = 30_000;
 
+function resolveWhatsAppRuntimeGroupPolicy(params: {
+  providerConfigPresent: boolean;
+  groupPolicy?: "open" | "allowlist" | "disabled";
+  defaultGroupPolicy?: "open" | "allowlist" | "disabled";
+}): {
+  groupPolicy: "open" | "allowlist" | "disabled";
+  providerMissingFallbackApplied: boolean;
+} {
+  return resolveRuntimeGroupPolicy({
+    providerConfigPresent: params.providerConfigPresent,
+    groupPolicy: params.groupPolicy,
+    defaultGroupPolicy: params.defaultGroupPolicy,
+    configuredFallbackPolicy: "open",
+    missingProviderFallbackPolicy: "allowlist",
+  });
+}
+
 export async function checkInboundAccessControl(params: {
   accountId: string;
   from: string;
@@ -82,7 +100,16 @@ export async function checkInboundAccessControl(params: {
   // - "disabled": block all group messages entirely
   // - "allowlist": only allow group messages from senders in groupAllowFrom/allowFrom
   const defaultGroupPolicy = cfg.channels?.defaults?.groupPolicy;
-  const groupPolicy = account.groupPolicy ?? defaultGroupPolicy ?? "open";
+  const { groupPolicy, providerMissingFallbackApplied } = resolveWhatsAppRuntimeGroupPolicy({
+    providerConfigPresent: cfg.channels?.whatsapp !== undefined,
+    groupPolicy: account.groupPolicy,
+    defaultGroupPolicy,
+  });
+  if (providerMissingFallbackApplied) {
+    logVerbose(
+      'whatsapp: channels.whatsapp is missing; defaulting groupPolicy to "allowlist" (group messages blocked until explicitly configured).',
+    );
+  }
   if (params.group && groupPolicy === "disabled") {
     logVerbose("Blocked group message (groupPolicy: disabled)");
     return {
@@ -191,3 +218,7 @@ export async function checkInboundAccessControl(params: {
     resolvedAccountId: account.accountId,
   };
 }
+
+export const __testing = {
+  resolveWhatsAppRuntimeGroupPolicy,
+};