[ GLSA 200903-24 ] Shadow: Privilege escalation

[GLSA]

Gentoo Linux Security Advisory

Title: Shadow: Privilege escalation (GLSA 200903-24)
Severity: high
Exploitable: local
Date: March 10, 2009
Bug(s): #251320
ID: 200903-24

Synopsis

An insecure temporary file usage in Shadow may allow local users to gain root privileges.

Background

Shadow is a set of tools to deal with user accounts.

Affected Packages

Package: sys-apps/shadow
Vulnerable: < 4.1.2.2
Unaffected: >= 4.1.2.2
Architectures: All supported architectures


Description

Paul Szabo reported a race condition in the "login" executable when setting up tty permissions.

Impact

A local attacker belonging to the "utmp" group could use symlink attacks to overwrite arbitrary files and possibly gain root privileges.

Workaround

There is no known workaround at this time.

Resolution

All Shadow users should upgrade to the latest version: