USN-802-2: Apache regression

19 August 2009

apache2 regression

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

  • Ubuntu 9.04
  • Ubuntu 8.10
  • Ubuntu 8.04 LTS
  • Ubuntu 6.06 LTS

Software Description

  • apache2


USN-802-1 fixed vulnerabilities in Apache. The upstream fix for CVE-2009-1891 introduced a regression that would cause Apache children to occasionally segfault when mod_deflate is used. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

It was discovered that mod_proxy_http did not properly handle a large amount of streamed data when used as a reverse proxy. A remote attacker could exploit this and cause a denial of service via memory resource consumption. This issue affected Ubuntu 8.04 LTS, 8.10 and 9.04. (CVE-2009-1890)

It was discovered that mod_deflate did not abort compressing large files when the connection was closed. A remote attacker could exploit this and cause a denial of service via CPU resource consumption. (CVE-2009-1891)

Update instructions

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

Ubuntu 9.04
apache2-mpm-event - 2.2.11-2ubuntu2.3
apache2-mpm-prefork - 2.2.11-2ubuntu2.3
apache2-mpm-worker - 2.2.11-2ubuntu2.3
apache2.2-common - 2.2.11-2ubuntu2.3
Ubuntu 8.10
apache2-mpm-event - 2.2.9-7ubuntu3.3
apache2-mpm-prefork - 2.2.9-7ubuntu3.3
apache2-mpm-worker - 2.2.9-7ubuntu3.3
apache2.2-common - 2.2.9-7ubuntu3.3
Ubuntu 8.04 LTS
apache2-mpm-event - 2.2.8-1ubuntu0.11
apache2-mpm-perchild - 2.2.8-1ubuntu0.11
apache2-mpm-prefork - 2.2.8-1ubuntu0.11
apache2-mpm-worker - 2.2.8-1ubuntu0.11
apache2.2-common - 2.2.8-1ubuntu0.11
Ubuntu 6.06 LTS
apache2-common - 2.0.55-4ubuntu2.8
apache2-mpm-perchild - 2.0.55-4ubuntu2.8
apache2-mpm-prefork - 2.0.55-4ubuntu2.8
apache2-mpm-worker - 2.0.55-4ubuntu2.8
libapr0 - 2.0.55-4ubuntu2.8

To update your system, please follow these instructions:

In general, a standard system upgrade is sufficient to effect the necessary changes.