Issued:

2013-02-21

Updated:

2013-02-21

RHSA-2013:0521 - Moderate: pam security, bug fix, and enhancement update

Synopsis

Moderate: pam security, bug fix, and enhancement update

Type/Severity

Security Advisory Moderate

Topic

Updated pam packages that fix two security issues, several bugs, and add various enhancements are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

Description

Pluggable Authentication Modules (PAM) provide a system whereby administrators can set up authentication policies without having to recompile programs to handle authentication.

A stack-based buffer overflow flaw was found in the way the pam_env module parsed users' "~/.pam_environment" files. If an application's PAM configuration contained "user_readenv=1" (this is not the default), a local attacker could use this flaw to crash the application or, possibly, escalate their privileges. (CVE-2011-3148)

A denial of service flaw was found in the way the pam_env module expanded certain environment variables. If an application's PAM configuration contained "user_readenv=1" (this is not the default), a local attacker could use this flaw to cause the application to enter an infinite loop. (CVE-2011-3149)

Red Hat would like to thank Kees Cook of the Google ChromeOS Team for reporting the CVE-2011-3148 and CVE-2011-3149 issues.

These updated pam packages include numerous bug fixes and enhancements. Space precludes documenting all of these changes in this advisory. Users are directed to the Red Hat Enterprise Linux 6.4 Technical Notes, linked to in the References, for information on the most significant of these changes.

All pam users are advised to upgrade to these updated packages, which contain backported patches to correct these issues and add these enhancements.

Solution

Before applying this update, make sure all previously-released errata relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/knowledge/articles/11258

Affected Products

Updated Packages

• pam-1.1.1-13.el6.s390x.rpm
• pam-debuginfo-1.1.1-13.el6.x86_64.rpm
• pam-devel-1.1.1-13.el6.i686.rpm
• pam-devel-1.1.1-13.el6.s390.rpm
• pam-devel-1.1.1-13.el6.s390x.rpm
• pam-1.1.1-13.el6.src.rpm
• pam-1.1.1-13.el6.x86_64.rpm
• pam-1.1.1-13.el6.ppc64.rpm
• pam-debuginfo-1.1.1-13.el6.s390.rpm
• pam-debuginfo-1.1.1-13.el6.i686.rpm
• pam-debuginfo-1.1.1-13.el6.ppc64.rpm
• pam-1.1.1-13.el6.ppc.rpm
• pam-devel-1.1.1-13.el6.ppc64.rpm
• pam-debuginfo-1.1.1-13.el6.s390x.rpm
• pam-1.1.1-13.el6.s390.rpm
• pam-debuginfo-1.1.1-13.el6.ppc.rpm
• pam-devel-1.1.1-13.el6.x86_64.rpm
• pam-devel-1.1.1-13.el6.ppc.rpm
• pam-1.1.1-13.el6.i686.rpm

Fixes

• This content is not included.BZ - 588893
• This content is not included.BZ - 673398
• This content is not included.BZ - 723297
• This content is not included.BZ - 746619
• This content is not included.BZ - 746620
• This content is not included.BZ - 750601
• This content is not included.BZ - 811168
• This content is not included.BZ - 811243
• This content is not included.BZ - 815516

CVEs

• CVE-2011-3149
• CVE-2011-3148

References

• https://access.redhat.com/security/updates/classification/#moderate
• This content is not included.This content is not included.https://access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/6/html/6.4_Technical_Notes/pam.html

Additional information

• The Red Hat security contact is This content is not included.secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.
• Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.