CVE-2009-0801: Squid Web Proxy Cache

Medium severity, CVSS 5.4. EPSS: 3.1% chance of exploitation in the next 30 days.

Squid, when transparent interception mode is enabled, uses the HTTP Host header to determine the remote endpoint, which allows remote attackers to bypass access controls for Flash, Java, Silverlight, and probably other technologies, and possibly communicate with restricted intranet sites, via a crafted web page that causes a client to send HTTP requests with a modified Host header.

Affected products

• Squid Squid Web Proxy Cache: version 2.7 only; version 2.7.stable5 only; version 2.7.stable6 only; version 3.0 only; version 3.0_pre1 only; version 3.0_pre2 only; …

Published 2009-03-04. Last modified 2026-06-16.