Ubuntu 8.04 LTS / 10.04 LTS / 10.10 / 11.04 : pam regression (USN-1140-2)
Medium Nessus Plugin ID 55103
SynopsisThe remote Ubuntu host is missing one or more security-related patches.
DescriptionUSN-1140-1 fixed vulnerabilities in PAM. A regression was found that caused cron to stop working with a 'Module is unknown' error. As a result, systems configured with automatic updates will not receive updates until cron is restarted, these updates are installed or the system is rebooted. This update fixes the problem.
We apologize for the inconvenience.
Marcus Granado discovered that PAM incorrectly handled configuration files with non-ASCII usernames. A remote attacker could use this flaw to cause a denial of service, or possibly obtain login access with a different users username. This issue only affected Ubuntu 8.04 LTS.
It was discovered that the PAM pam_xauth, pam_env and pam_mail modules incorrectly handled dropping privileges when performing operations. A local attacker could use this flaw to read certain arbitrary files, and access other sensitive information. (CVE-2010-3316, CVE-2010-3430, CVE-2010-3431, CVE-2010-3435)
It was discovered that the PAM pam_namespace module incorrectly cleaned the environment during execution of the namespace.init script. A local attacker could use this flaw to possibly gain privileges. (CVE-2010-3853)
It was discovered that the PAM pam_xauth module incorrectly handled certain failures. A local attacker could use this flaw to delete certain unintended files. (CVE-2010-4706)
It was discovered that the PAM pam_xauth module incorrectly verified certain file properties. A local attacker could use this flaw to cause a denial of service. (CVE-2010-4707).
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 and / or libpam0g packages.