CVE-2012-2213 Auth bypass in n/a
Remote attackers can bypass CONNECT method access controls in Squid by manipulating the Host header, potentially allowing unauthorized proxy usage.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2012-2213?
CVE-2012-2213 is a medium-severity authentication bypass vulnerability in Squid-Cache Squid, published on 28 Apr 2012. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Squid 3.1.9 allows remote attackers to bypass the access configuration for the CONNECT method by providing an arbitrary allowed hostname in the Host HTTP header. NOTE: this issue might not be reproducible, because the researcher is unable to provide a squid.conf file for a vulnerable system, and the observed behavior is consistent with a squid.conf file that was (perhaps inadvertently) designed to allow access based on a "req_header Host" acl regex that matches www.uol.com.br
Weakness: CWE-264
Which versions are affected by CVE-2012-2213?
It affects 1 product.
Products include Squid-Cache Squid.
How do I fix CVE-2012-2213?
No fix has been published for CVE-2012-2213 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2012-2213 being exploited?
There is no known exploitation of CVE-2012-2213 in the wild and no public exploit code.
Other vulnerabilities in Squid-Cache Squid
- CVE-2025-62168 Squid vulnerable to information disclosure via authentication credential leakage in error handling
- CVE-2025-54574 Squid's URN Handling can lead to Buffer Overflow
- CVE-2026-33526 Squid vulnerable to Denial of Service in ICP Request handling
- CVE-2026-32748 Squid has Denial of Service in ICP Response handling
- CVE-2023-50269 SQUID-2023:10 Denial of Service in HTTP Request parsing
Sources
Also known as GHSA-4xhr-2rmp-vfjq.