The client in OpenSSH before 7.2 mishandles failed cookie generation for untrusted X11 forwarding and relies on the local X11 server for access-control decisions, which allows remote X11 clients to trigger a fallback and obtain trusted X11 forwarding privileges by leveraging configuration issues on this X11 server, as demonstrated by lack of the SECURITY extension on this X11 server.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Openssh | Openbsd | * | 7.2 (excluding) |