CVE-2011-3639 The mod_proxy module in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x before 2.2.18, when the Revision 1179239 patch is in place, do

What is CVE-2011-3639?

CVE-2011-3639 is a medium-severity vulnerability in Apache Http Server, published on 30 Nov 2011.

Official description

The mod_proxy module in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x before 2.2.18, when the Revision 1179239 patch is in place, does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers by using the HTTP/0.9 protocol with a malformed URI containing an initial @ (at sign) character. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-3368.

Weakness: CWE-20

Which versions are affected by CVE-2011-3639?

It affects 10 products.

Products include Apache Http Server, Apache Http Server2.0a1, Apache Http Server2.0a2, Apache Http Server2.0a3, Apache Http Server2.0a4, Apache Http Server2.0a5 and 4 more.

How do I fix CVE-2011-3639?

Upgrade to a fixed version.

Is CVE-2011-3639 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2011-3639 exists.

Public exploit code: 1 Exploit-DB entry.

Other vulnerabilities in Apache Http Server

• CVE-2021-42013 Apache HTTP Server Path Traversal Exploited Critical 9.8
• CVE-2024-38475 Apache HTTP Server Improper Escaping of Output Exploited Critical 9.1
• CVE-2021-40438 Apache HTTP Server-Side Request Forgery (SSRF) Exploited Critical 9.0
• CVE-2019-0211 Apache HTTP Server Privilege Escalation Exploited High 7.8
• CVE-2021-41773 Apache HTTP Server Path Traversal Exploited High 7.5

All Apache Http Server vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2011-3639, GHSA-rqg3-pfxx-wwq3.