SB2011012403 - Multiple vulnerabilities in git.kernel linux-pam

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Input validation error (CVE-ID: CVE-2010-3430)

The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

The privilege-dropping implementation in the (1) pam_env and (2) pam_mail modules in Linux-PAM (aka pam) 1.1.2 does not perform the required setfsgid and setgroups system calls, which might allow local users to obtain sensitive information by leveraging unintended group permissions, as demonstrated by a symlink attack on the .pam_environment file in a user's home directory. NOTE: this vulnerability exists because of an incomplete fix for CVE-2010-3435.

2) Input validation error (CVE-ID: CVE-2010-3431)

The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

The privilege-dropping implementation in the (1) pam_env and (2) pam_mail modules in Linux-PAM (aka pam) 1.1.2 does not check the return value of the setfsuid system call, which might allow local users to obtain sensitive information by leveraging an unintended uid, as demonstrated by a symlink attack on the .pam_environment file in a user's home directory. NOTE: this vulnerability exists because of an incomplete fix for CVE-2010-3435.

Remediation

Install update from vendor's website.

References

• http://git.altlinux.org/people/ldv/packages/?p=pam.git;a=commit;h=843807a3a90f52e7538be756616510730a24739a
• http://openwall.com/lists/oss-security/2010/09/21/10
• http://openwall.com/lists/oss-security/2010/09/21/3
• http://openwall.com/lists/oss-security/2010/09/21/8
• http://openwall.com/lists/oss-security/2010/09/21/9
• http://openwall.com/lists/oss-security/2010/09/27/10
• http://openwall.com/lists/oss-security/2010/09/27/4
• http://openwall.com/lists/oss-security/2010/09/27/5
• http://openwall.com/lists/oss-security/2010/09/27/7
• http://openwall.com/lists/oss-security/2010/10/03/1
• http://openwall.com/lists/oss-security/2010/10/25/2
• http://secunia.com/advisories/49711
• http://security.gentoo.org/glsa/glsa-201206-31.xml
• http://www.openwall.com/lists/oss-security/2010/09/21/11
• http://www.openwall.com/lists/oss-security/2010/09/24/2
• https://bugzilla.redhat.com/show_bug.cgi?id=641361