security: fix CVE-2025-52553 (#15289)

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

authentik/providers/rac/consumer_client.py

@@ -66,7 +66,10 @@ class RACClientConsumer(AsyncWebsocketConsumer):
     def init_outpost_connection(self):
         """Initialize guac connection settings"""
         self.token = (
-            ConnectionToken.filter_not_expired(token=self.scope["url_route"]["kwargs"]["token"])
+            ConnectionToken.filter_not_expired(
+                token=self.scope["url_route"]["kwargs"]["token"],
+                session__session__session_key=self.scope["session"].session_key,
+            )
             .select_related("endpoint", "provider", "session", "session__user")
             .first()
         )

authentik/providers/rac/tests/test_views.py

@@ -87,3 +87,22 @@ class TestRACViews(APITestCase):
         )
         body = loads(flow_response.content)
         self.assertEqual(body["component"], "ak-stage-access-denied")
+
+    def test_different_session(self):
+        """Test request"""
+        self.client.force_login(self.user)
+        response = self.client.get(
+            reverse(
+                "authentik_providers_rac:start",
+                kwargs={"app": self.app.slug, "endpoint": str(self.endpoint.pk)},
+            )
+        )
+        self.assertEqual(response.status_code, 302)
+        flow_response = self.client.get(
+            reverse("authentik_api:flow-executor", kwargs={"flow_slug": self.flow.slug})
+        )
+        body = loads(flow_response.content)
+        next_url = body["to"]
+        self.client.logout()
+        final_response = self.client.get(next_url)
+        self.assertEqual(final_response.url, reverse("authentik_core:if-user"))

authentik/providers/rac/views.py

@@ -68,7 +68,10 @@ class RACInterface(InterfaceView):
 
     def dispatch(self, request: HttpRequest, *args: Any, **kwargs: Any) -> HttpResponse:
         # Early sanity check to ensure token still exists
-        token = ConnectionToken.filter_not_expired(token=self.kwargs["token"]).first()
+        token = ConnectionToken.filter_not_expired(
+            token=self.kwargs["token"],
+            session__session__session_key=request.session.session_key,
+        ).first()
         if not token:
             return redirect("authentik_core:if-user")
         self.token = token

website/docs/security/cves/CVE-2025-52553.md

@@ -0,0 +1,27 @@
+# CVE-2025-52553
+
+_Reported by [SPIEGEL-Verlag](https://gruppe.spiegel.de)_
+
+## Insufficient Session verification for Remote Access Control endpoint access
+
+### Summary
+
+After authorizing access to a RAC endpoint, authentik creates a token which is used for a single connection and is sent to the client in the URL. This token is intended to only be valid for the session of the user who authorized the connection, however this check is currently missing.
+
+### Patches
+
+authentik 2025.4.3 and 2025.6.3 fix this issue.
+
+### Impact
+
+When for example using RAC during a screenshare, a malicious user could access the same session by copying the URL from the shown browser.
+
+### Workarounds
+
+As a workaround it is recommended to decrease the duration a token is valid for (in the RAC Provider settings, set **Connection expiry** to `minutes=5` for example). We also recommend enabling the option **Delete authorization on disconnect**.
+
+### For more information
+
+If you have any questions or comments about this advisory:
+
+- Email us at [security@goauthentik.io](mailto:security@goauthentik.io).

website/sidebars/docs.mjs

@@ -710,7 +710,7 @@ const items = [
                     {
                         type: "category",
                         label: "2025",
-                        items: ["security/cves/CVE-2025-29928"],
+                        items: ["security/cves/CVE-2025-52553", "security/cves/CVE-2025-29928"],
                     },
                     {
                         type: "category",