diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6e25911d8fd..50679d405ca 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Control UI/Talk: fix Talk (OpenAI Realtime WebRTC) CORS failure by stripping server-side-only attribution headers (`originator`, `version`, `User-Agent`) from browser offer headers; `api.openai.com/v1/realtime/calls` only allows `authorization` and `content-type` in its CORS preflight, so forwarding these headers caused the browser SDP exchange to fail. Fixes #76435. Thanks @hclsys.
 - Plugins/onboarding: trust optional official plugin and web-search installs selected from the official catalog so npm security scanning treats them like other source-linked official install paths. Thanks @vincentkoc.
 - Microsoft Teams: persist sent-message markers across Gateway restarts so follow-up replies to recent bot messages keep resolving the original conversation instead of dropping out after restart, with marker TTLs preserved on best-effort recovery. (#75585) Thanks @amknight.
 - Matrix: persist pending approval reaction targets across Gateway restarts so room approvers can still approve or deny outstanding prompts after OpenClaw comes back online. (#75586) Thanks @amknight.
diff --git a/extensions/openai/realtime-voice-provider.test.ts b/extensions/openai/realtime-voice-provider.test.ts
index 197cfb7e209..b5554b65b05 100644
--- a/extensions/openai/realtime-voice-provider.test.ts
+++ b/extensions/openai/realtime-voice-provider.test.ts
@@ -192,14 +192,12 @@ describe("buildOpenAIRealtimeVoiceProvider", () => {
       transport: "webrtc-sdp",
       clientSecret: "client-secret-123",
       offerUrl: "https://api.openai.com/v1/realtime/calls",
-      offerHeaders: {
-        originator: "openclaw",
-        version: "2026.3.22",
-      },
     });
-    expect((session as { offerHeaders?: Record<string, string> }).offerHeaders).not.toHaveProperty(
-      "User-Agent",
-    );
+    // originator, version, and User-Agent are server-side attribution headers; they
+    // must not be forwarded to the browser so that the browser's direct SDP POST to
+    // api.openai.com passes the CORS preflight (only authorization,content-type
+    // allowed — #76435). All three are filtered, leaving no browser offer headers.
+    expect((session as { offerHeaders?: Record<string, string> }).offerHeaders).toBeUndefined();
   });
 
   it("resolves keychain OPENAI_API_KEY refs before creating browser sessions", async () => {
diff --git a/extensions/openai/realtime-voice-provider.ts b/extensions/openai/realtime-voice-provider.ts
index b2deeb9e054..c0556eb9594 100644
--- a/extensions/openai/realtime-voice-provider.ts
+++ b/extensions/openai/realtime-voice-provider.ts
@@ -731,8 +731,12 @@ function resolveOpenAIRealtimeBrowserOfferHeaders(): Record<string, string> | un
     transport: "http",
     defaultHeaders: {},
   });
+  // Strip server-side-only attribution headers: browser direct fetches to
+  // api.openai.com fail CORS preflight when these are present (only
+  // authorization,content-type are allowed by the endpoint's CORS policy).
+  const SERVER_ONLY_HEADERS = new Set(["user-agent", "originator", "version"]);
   const browserHeaders = Object.fromEntries(
-    Object.entries(headers ?? {}).filter(([key]) => key.toLowerCase() !== "user-agent"),
+    Object.entries(headers ?? {}).filter(([key]) => !SERVER_ONLY_HEADERS.has(key.toLowerCase())),
   );
   return Object.keys(browserHeaders).length > 0 ? browserHeaders : undefined;
 }