Ubuntu Security Notice 901-1 – It was discovered that Squid incorrectly handled certain auth headers. A remote attacker could exploit this with a specially-crafted auth header and cause Squid to go into an infinite loop, resulting in a denial of service. This issue only affected Ubuntu 8.10, 9.04 and 9.10. It was discovered that Squid incorrectly handled certain DNS packets. A remote attacker could exploit this with a specially-crafted DNS packet and cause Squid to crash, resulting in a denial of service.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/86368/USN-901-1.txt
Source: https://packetstormsecurity.com/files/86368/Ubuntu-Security-Notice-901-1.html