[ GLSA 201201-12 ] Tor: Multiple vulnerabilities

[GLSA]

Gentoo Linux Security Advisory

Title: Tor: Multiple vulnerabilities (GLSA 201201-12)
Severity: normal
Exploitable: remote
Date: January 23, 2012
Bug(s): #388769, #394969
ID: 201201-12

Synopsis

Multiple vulnerabilities have been found in Tor, the most severe of
which may allow a remote attacker to execute arbitrary code.


Background

Tor is an implementation of second generation Onion Routing, a
connection-oriented anonymizing communication service.


Affected Packages

Package: net-misc/tor
Vulnerable: < 0.2.2.35
Unaffected: >= 0.2.2.35
Architectures: All supported architectures


Description

Multiple vulnerabilities have been discovered in Tor:

• When configured as client or bridge, Tor uses the same TLS
  certificate chain for all outgoing connections (CVE-2011-2768).
  
• When configured as a bridge, Tor relays can distinguish incoming
  bridge connections from client connections (CVE-2011-2769).
  
• An error in or/buffers.c could result in a heap-based buffer overflow
  (CVE-2011-2778).
  

Impact

A remote attacker could possibly execute arbitrary code or cause a
Denial of Service. Furthermore, a remote relay the user is directly
connected to may be able to disclose anonymous information about that
user or enumerate bridges in the user's connection.


Workaround

There is no known workaround at this time.

Resolution

All Tor users should upgrade to the latest version: