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.
{ "ubuntu_priority": "low", "availability": "No subscription required", "binaries": [ { "binary_name": "openssh-client", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-client-dbgsym", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-client-udeb", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-client-udeb-dbgsym", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-server", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-server-dbgsym", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-server-udeb", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-server-udeb-dbgsym", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-sftp-server", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "openssh-sftp-server-dbgsym", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "ssh", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "ssh-askpass-gnome", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "ssh-askpass-gnome-dbgsym", "binary_version": "1:6.6p1-2ubuntu2.7" }, { "binary_name": "ssh-krb5", "binary_version": "1:6.6p1-2ubuntu2.7" } ] }
{ "ubuntu_priority": "low", "availability": "No subscription required", "binaries": [ { "binary_name": "openssh-client", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-client-dbgsym", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-client-ssh1", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-client-ssh1-dbgsym", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-client-udeb", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-client-udeb-dbgsym", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-server", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-server-dbgsym", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-server-udeb", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-server-udeb-dbgsym", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-sftp-server", "binary_version": "1:7.2p2-4" }, { "binary_name": "openssh-sftp-server-dbgsym", "binary_version": "1:7.2p2-4" }, { "binary_name": "ssh", "binary_version": "1:7.2p2-4" }, { "binary_name": "ssh-askpass-gnome", "binary_version": "1:7.2p2-4" }, { "binary_name": "ssh-askpass-gnome-dbgsym", "binary_version": "1:7.2p2-4" }, { "binary_name": "ssh-krb5", "binary_version": "1:7.2p2-4" } ] }