SB2011111706 - Path traversal in FreeBSD

Description

This security bulletin contains information about 1 security vulnerability.

1) Path traversal (CVE-ID: CVE-2011-4122)

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to input validation error when processing directory traversal sequences in openpam_configure.c in OpenPAM before r478 on FreeBSD 8.1. A remote authenticated attacker can send a specially crafted HTTP request and local users to load arbitrary DSOs and gain privileges via a . (dot dot) in the service_name argument to the pam_start function, as demonstrated by a . in the -c option to kcheckpass.

Remediation

Cybersecurity Help is not aware of any official remediation provided by the vendor.

References

• http://c-skills.blogspot.com/2011/11/openpam-trickery.html
• http://openwall.com/lists/oss-security/2011/12/07/3
• http://openwall.com/lists/oss-security/2011/12/08/9
• http://osvdb.org/76945
• http://secunia.com/advisories/46756
• http://secunia.com/advisories/46804
• http://stealth.openwall.net/xSports/pamslam
• http://trac.des.no/openpam/changeset/478/trunk/lib/openpam_configure.c
• https://exchange.xforce.ibmcloud.com/vulnerabilities/71205