Ubuntu 8.04 LTS / 10.04 LTS / 10.10 / 11.04 / 11.10 : pam vulnerabilities (USN-1237-1)
Medium Nessus Plugin ID 56629
SynopsisThe remote Ubuntu host is missing a security-related patch.
DescriptionKees Cook discovered that the PAM pam_env module incorrectly handled certain malformed environment files. A local attacker could use this flaw to cause a denial of service, or possibly gain privileges. The default compiler options for affected releases should reduce the vulnerability to a denial of service. (CVE-2011-3148)
Kees Cook discovered that the PAM pam_env module incorrectly handled variable expansion. A local attacker could use this flaw to cause a denial of service. (CVE-2011-3149)
Stephane Chazelas discovered that the PAM pam_motd module incorrectly cleaned the environment during execution of the motd scripts. In certain environments, a local attacker could use this to execute arbitrary code as root, and gain privileges.
Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
SolutionUpdate the affected libpam-modules package.