Ubuntu: 1140-2 Moderate: PAM Misconfigurations Disrupt Scheduled Tasks

ubuntu

May 31, 2011

The USN-1140-1 PAM update caused cron to stop working.

Summary

The USN-1140-1 PAM update caused cron to stop working.

Software Description:

- pam: Pluggable Authentication Modules

Details:

USN-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.

Original advisory details:

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. (CVE-2009-0887)

It was discovered that the PAM pam_xauth, pam_env and pam_mail modules

incorrectly handled dropping privileges when performing operations. A local

atta...

Read the Full Advisory

Topics Covered

security advisory moderate ubuntu pam regression cron issue

Update Instructions

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 11.04:
  libpam-modules                  1.1.2-2ubuntu8.3
  libpam0g                        1.1.2-2ubuntu8.3

Ubuntu 10.10:
  libpam-modules                  1.1.1-4ubuntu2.3
  libpam0g                        1.1.1-4ubuntu2.3

Ubuntu 10.04 LTS:
  libpam-modules                  1.1.1-2ubuntu5.3
  libpam0g                        1.1.1-2ubuntu5.3

Ubuntu 8.04 LTS:
  libpam-modules                  0.99.7.1-5ubuntu6.4
  libpam0g                        0.99.7.1-5ubuntu6.4

In general, a standard system update will make all the necessary changes.