AIX OpenSSH Advisory : openssh_advisory9.asc
High Nessus Plugin ID 95477
SynopsisThe remote AIX host has a version of OpenSSH installed that is affected by multiple vulnerabilities.
DescriptionThe remote AIX host has a version of OpenSSH installed that is affected by the following vulnerabilities :
- An elevation of privilege vulnerability exists in the do_setup_env() function within file session.c when handling user-supplied environmental variables. A local attacker can exploit this to gain elevated privileges by triggering a crafted environment for the /bin/login program. This vulnerability requires that the UseLogin feature is enabled and that PAM is configured to read .pam_environment files in user home directories.
- A flaw exists when handling authentication requests that involve overly long passwords due to returning shorter response times for requests for invalid users than for valid users. An unauthenticated, remote attacker can exploit this to enumerate valid usernames by conducting a timing attack. (CVE-2016-6210)
- A denial of service vulnerability exists in the auth_password() function within auth-passwd.c due to a a failure to limit password lengths. An unauthenticated, remote attacker can exploit this, via overly long passwords, to cause the excessive consumption of CPU resources. (CVE-2016-6515)
SolutionA fix is available and can be downloaded from the IBM AIX website.