Ubuntu Security Notice USN-802-1 – 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. 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.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/79142/USN-802-1.txt
Source: https://packetstormsecurity.com/files/79142/Ubuntu-Security-Notice-802-1.html