Ubuntu 12.04 LTS : pam regression (USN-2935-3)

Medium Nessus Plugin ID 90021


The remote Ubuntu host is missing a security-related patch.


USN-2935-1 fixed vulnerabilities in PAM. The updates contained a packaging change that prevented upgrades in certain multiarch environments. USN-2935-2 intended to fix the problem but was incomplete for Ubuntu 12.04 LTS. This update fixes the problem in Ubuntu 12.04 LTS.

We apologize for the inconvenience.

It was discovered that the PAM pam_userdb module incorrectly used a case-insensitive method when comparing hashed passwords. A local attacker could possibly use this issue to make brute-force attacks easier. This issue only affected Ubuntu 12.04 LTS and Ubuntu 14.04 LTS. (CVE-2013-7041)

Sebastian Krahmer discovered that the PAM pam_timestamp module incorrectly performed filtering. A local attacker could use this issue to create arbitrary files, or possibly bypass authentication. This issue only affected Ubuntu 12.04 LTS and Ubuntu 14.04 LTS. (CVE-2014-2583)

Sebastien Macke discovered that the PAM pam_unix module incorrectly handled large passwords. A local attacker could possibly use this issue in certain environments to enumerate usernames or cause a denial of service. (CVE-2015-3238).

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.


Update the affected libpam-modules package.

Plugin Details

Severity: Medium

ID: 90021

File Name: ubuntu_USN-2935-3.nasl

Version: $Revision: 2.5 $

Type: local

Agent: unix

Published: 2016/03/18

Modified: 2016/12/01

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 5.8

Temporal Score: 3.9

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:N

Temporal Vector: CVSS2#E:U/RL:OF/RC:UC


Base Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:libpam-modules, cpe:/o:canonical:ubuntu_linux:12.04:-:lts

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2016/03/17

Reference Information

CVE: CVE-2013-7041, CVE-2014-2583, CVE-2015-3238

OSVDB: 100873, 104926, 123767

USN: 2935-3