GLSA 201705-15: sudo: Privilege escalation

http://security.gentoo.org/

Severity:	high
Title:	sudo: Privilege escalation
Date:	05/30/2017
Bugs:	#620182
ID:	201705-15

Synopsis

A vulnerability in sudo allows local users to gain root privileges.

Background

sudo (su “do”) allows a system administrator to delegate authority to give certain users (or groups of users) the ability to run some (or all) commands as root or another user while providing an audit trail of the commands and their arguments.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
app-admin/sudo	< 1.8.20_p1	>= 1.8.20_p1	All supported architectures

Description

Qualys discovered a vulnerability in sudo’s get_process_ttyname() for Linux, that via sudo_ttyname_scan() can be directed to use a user-controlled, arbitrary tty device during its traversal of “/dev” by utilizing the world-writable /dev/shm.

Impact

A local attacker can pretend that his tty is any character device on the filesystem, and after two race conditions, an attacker can pretend that the controlled tty is any file on the filesystem allowing for privilege escalation

Workaround

There is no known workaround at this time.

Resolution

All sudo users should upgrade to the latest version:

      # emerge --sync
      # emerge --ask --oneshot --verbose ">=app-admin/sudo-1.8.20_p1"

References

CVE-2017-1000367

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-201705-15.xml

Concerns?

Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.