[ GLSA 200606-02 ] shadow: Privilege escalation

[GLSA]

Gentoo Linux Security Advisory

Title: shadow: Privilege escalation (GLSA 200606-02)
Severity: normal
Exploitable: local
Date: June 07, 2006
Bug(s): #133615
ID: 200606-02

Synopsis

A security issue in shadow allows a local user to perform certain actions with escalated privileges.

Background

shadow provides a set of utilities to deal with user accounts.

Affected Packages

Package: sys-apps/shadow
Vulnerable: < 4.0.15-r2
Unaffected: >= 4.0.15-r2
Architectures: All supported architectures


Description

When the mailbox is created in useradd, the "open()" function does not receive the three arguments it expects while O_CREAT is present, which leads to random permissions on the created file, before fchmod() is executed.

Impact

Depending on the random permissions given to the mailbox file which is at this time owned by root, a local user may be able to open this file for reading or writing, or even executing it, maybe as the root user.

Workaround

There is no known workaround at this time.

Resolution

All shadow users should upgrade to the latest version: