LibVNCServer: Authentication bypass — GLSA 200608-05

VNC servers created with LibVNCServer accept insecure protocol types, even when the server does not offer it, resulting in unauthorized access to the server.

Affected Packages

net-libs/libvncserver on all architectures
Affected versions < 0.8.2
Unaffected versions >= 0.8.2

Background

LibVNCServer is a GPL'ed library for creating VNC servers.

Description

LibVNCServer fails to properly validate protocol types effectively letting users decide what protocol to use, such as "Type 1 - None". LibVNCServer will accept this security type, even if it is not offered by the server.

Impact

An attacker could use this vulnerability to gain unauthorized access with the privileges of the user running the VNC server.

Workaround

There is no known workaround at this time.

Resolution

All LibVNCServer users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-libs/libvncserver-0.8.2"

References

Release Date
August 04, 2006

Latest Revision
August 04, 2006: 01

Severity
high

Exploitable
remote

Bugzilla entries