OpenSSH < 5.0 X11 Forwarding Local Session Hijacking
Medium Nessus Network Monitor Plugin ID 4459
SynopsisThe remote SSH service is prone to an X11 session hijacking vulnerability.
DescriptionAccording to its banner, the version of SSH installed on the remote host is older than 5.0. Such versions may allow a local user to hijack X11 sessions because it improperly binds TCP ports on the local IPv6 interface if the corresponding ports on the IPv4 interface are in use.
Note: PVS has solely relied on the banner of the SSH client to perform this check. Any backported patches or workarounds such as recompiling or edited configurations are not observable through the banner.
SolutionUpgrade to version 5.0 or higher.