USN-177-1: Apache 2 vulnerabilities

Ubuntu Security Notice USN-177-1

7th September, 2005

apache2, libapache-mod-ssl vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 5.04
  • Ubuntu 4.10

Details

Apache did not honour the "SSLVerifyClient require" directive within a
<Location> block if the surrounding <VirtualHost> block contained a
directive "SSLVerifyClient optional". This allowed clients to bypass
client certificate validation on servers with the above configuration.
(CAN-2005-2700)

Filip Sneppe discovered a Denial of Service vulnerability in the byte
range filter handler. By requesting certain large byte ranges, a
remote attacker could cause memory exhaustion in the server.
(CAN-2005-2728)

The updated libapache-mod-ssl also fixes two older Denial of Service
vulnerabilities: A format string error in the ssl_log() function which
could be exploited to crash the server (CAN-2004-0700), and a flaw in
the SSL cipher negotiation which could be exploited to terminate a
session (CAN-2004-0885). Please note that Apache 1.3 and
libapache-mod-ssl are not officially supported (they are in the
"universe" component of the Ubuntu archive).

Update instructions

The problem can be corrected by updating your system to the following package version:

Ubuntu 5.04:
apache2-mpm-worker
apache2-mpm-perchild
apache2-mpm-threadpool
apache2-mpm-prefork
libapache-mod-ssl
Ubuntu 4.10:
apache2-mpm-worker
apache2-mpm-perchild
apache2-mpm-threadpool
apache2-mpm-prefork
libapache-mod-ssl

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

None

References

CVE-2005-2700, CVE-2005-2728