USN-77-1: Squid vulnerabilities

8 February 2005

squid vulnerabilities

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

  • Ubuntu 4.10

Software Description


A possible authentication bypass was discovered in the LDAP authentication backend. LDAP ignores leading and trailing whitespace in search filters. This could possibly be abused to bypass explicit access controls or confuse accounting when using several variants of the login name. (CAN-2005-0173)

Previous Squid versions were not strict enough while parsing HTTP requests and responses. Various violations of the HTTP protocol, such as multiple Content-Length header lines, invalid “Carriage Return” characters, and HTTP header names containing whitespace, led to cache pollution and could possibly be exploited to deliver wrong content to clients. (CAN-2005-0174)

Squid was susceptible to a cache poisoning attack called “HTTP response splitting”, where false replies are injected in the HTTP stream. This allowed malicious web servers to forge wrong cache content for arbitrary web sites, which was then delivered to Squid clients. (CAN-2005-0175)

The FSC Vulnerability Research Team discovered a buffer overflow in the WCCP handling protocol. By sending an overly large WCCP packet, a remote attacker could crash the Squid server, and possibly even execute arbitrary code with the privileges of the “proxy” user. (CAN-2005-0211)

Update instructions

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

Ubuntu 4.10

To update your system, please follow these instructions: