fix(gateway): stop webchat route inheritance on channel sessions (#39175, thanks @widingmarcus-cyber)

Co-authored-by: Marcus Widing <widing.marcus@gmail.com>

CHANGELOG.md

@@ -288,6 +288,7 @@ Docs: https://docs.openclaw.ai
 - Telegram/polling conflict recovery: reset the polling `webhookCleared` latch on `getUpdates` 409 conflicts so webhook cleanup re-runs on restart cycles and polling avoids infinite conflict loops. (#39205) Thanks @amittell.
 - Heartbeat/requests-in-flight scheduling: stop advancing `nextDueMs` and avoid immediate `scheduleNext()` timer overrides on requests-in-flight skips, so wake-layer retry cooldowns are honored and heartbeat cadence no longer drifts under sustained contention. (#39182) Thanks @MumuTW.
 - Memory/SQLite contention resilience: re-apply `PRAGMA busy_timeout` on every sync-store and QMD connection open so process restarts/reopens no longer revert to immediate `SQLITE_BUSY` failures under lock contention. (#39183) Thanks @MumuTW.
+- Gateway/webchat route safety: block webchat/control-ui clients from inheriting stored external delivery routes on channel-scoped sessions (while preserving route inheritance for UI/TUI clients), preventing cross-channel leakage from scoped chats. (#39175) Thanks @widingmarcus-cyber.
 
 ## 2026.3.2
 

src/gateway/server-methods/chat.directive-tags.test.ts

@@ -797,4 +797,92 @@ describe("chat directive tag stripping for non-streaming final payloads", () =>
       }),
     );
   });
+
+  it("chat.send does not inherit external routes for webchat clients on channel-scoped sessions", async () => {
+    createTranscriptFixture("openclaw-chat-send-webchat-channel-scoped-no-inherit-");
+    mockState.finalText = "ok";
+    mockState.sessionEntry = {
+      deliveryContext: {
+        channel: "imessage",
+        to: "+8619800001234",
+        accountId: "default",
+      },
+      lastChannel: "imessage",
+      lastTo: "+8619800001234",
+      lastAccountId: "default",
+    };
+    const respond = vi.fn();
+    const context = createChatContext();
+
+    // Webchat client accessing an iMessage channel-scoped session should NOT
+    // inherit the external delivery route. Fixes #38957.
+    await runNonStreamingChatSend({
+      context,
+      respond,
+      idempotencyKey: "idem-webchat-channel-scoped-no-inherit",
+      client: {
+        connect: {
+          client: {
+            mode: GATEWAY_CLIENT_MODES.WEBCHAT,
+            id: "openclaw-webchat",
+          },
+        },
+      } as unknown,
+      sessionKey: "agent:main:imessage:direct:+8619800001234",
+      deliver: true,
+      expectBroadcast: false,
+    });
+
+    expect(mockState.lastDispatchCtx).toEqual(
+      expect.objectContaining({
+        OriginatingChannel: "webchat",
+        OriginatingTo: undefined,
+        ExplicitDeliverRoute: false,
+        AccountId: undefined,
+      }),
+    );
+  });
+
+  it("chat.send still inherits external routes for UI clients on channel-scoped sessions", async () => {
+    createTranscriptFixture("openclaw-chat-send-ui-channel-scoped-inherit-");
+    mockState.finalText = "ok";
+    mockState.sessionEntry = {
+      deliveryContext: {
+        channel: "imessage",
+        to: "+8619800001234",
+        accountId: "default",
+      },
+      lastChannel: "imessage",
+      lastTo: "+8619800001234",
+      lastAccountId: "default",
+    };
+    const respond = vi.fn();
+    const context = createChatContext();
+
+    await runNonStreamingChatSend({
+      context,
+      respond,
+      idempotencyKey: "idem-ui-channel-scoped-inherit",
+      client: {
+        connect: {
+          client: {
+            mode: GATEWAY_CLIENT_MODES.UI,
+            id: "openclaw-tui",
+          },
+        },
+      } as unknown,
+      sessionKey: "agent:main:imessage:direct:+8619800001234",
+      deliver: true,
+      expectBroadcast: false,
+    });
+
+    expect(mockState.lastDispatchCtx).toEqual(
+      expect.objectContaining({
+        OriginatingChannel: "imessage",
+        OriginatingTo: "+8619800001234",
+        ExplicitDeliverRoute: true,
+        AccountId: "default",
+      }),
+    );
+  });
 });

src/gateway/server-methods/chat.ts

@@ -32,11 +32,7 @@ import {
 } from "../chat-abort.js";
 import { type ChatImageContent, parseMessageWithAttachments } from "../chat-attachments.js";
 import { stripEnvelopeFromMessage, stripEnvelopeFromMessages } from "../chat-sanitize.js";
-import {
-  GATEWAY_CLIENT_CAPS,
-  GATEWAY_CLIENT_MODES,
-  hasGatewayClientCap,
-} from "../protocol/client-info.js";
+import { GATEWAY_CLIENT_CAPS, hasGatewayClientCap } from "../protocol/client-info.js";
 import {
   ErrorCodes,
   errorShape,
@@ -168,22 +164,22 @@ function resolveChatSendOriginatingRoute(params: {
     !isChannelScopedSession &&
     typeof sessionScopeParts[1] === "string" &&
     sessionChannelHint === routeChannelCandidate;
-  const isFromWebchatClient =
-    isWebchatClient(params.client) || params.client?.mode === GATEWAY_CLIENT_MODES.UI;
+  const isFromWebchatClient = isWebchatClient(params.client);
   const configuredMainKey = (params.mainKey ?? "main").trim().toLowerCase();
   const isConfiguredMainSessionScope =
     normalizedSessionScopeHead.length > 0 && normalizedSessionScopeHead === configuredMainKey;
 
-  // Keep explicit delivery for channel-scoped sessions, but refuse to inherit
-  // stale external routes for shared-main and other channel-agnostic webchat/UI
-  // turns where the session key does not encode the user's current target.
+  // Webchat/Control UI clients never inherit external delivery routes, even when
+  // accessing channel-scoped sessions. External routes are only for non-webchat
+  // clients where the session key explicitly encodes an external target.
   // Preserve the old configured-main contract: any connected non-webchat client
   // may inherit the last external route even when client metadata is absent.
   const canInheritDeliverableRoute = Boolean(
+    !isFromWebchatClient &&
     sessionChannelHint &&
     sessionChannelHint !== INTERNAL_MESSAGE_CHANNEL &&
     ((!isChannelAgnosticSessionScope && (isChannelScopedSession || hasLegacyChannelPeerShape)) ||
-      (isConfiguredMainSessionScope && params.hasConnectedClient && !isFromWebchatClient)),
+      (isConfiguredMainSessionScope && params.hasConnectedClient)),
   );
   const hasDeliverableRoute =
     canInheritDeliverableRoute &&