What’s Vulnerable › Vulnerabilities

CVE-2011-3639

• Severity: medium (CVSS 4.3 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 49.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2011-11-30 · updated 2026-06-16
• Weakness: CWE-20

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.

Affected products

• Apache HTTP Server: 2.0.11, 2.0.12, 2.0.13, 2.0.14, 2.0.15, 2.0.16 (+61)
• Apache Http Server2.0A1: all versions
• Apache Http Server2.0A2: all versions
• Apache Http Server2.0A3: all versions
• Apache Http Server2.0A4: all versions
• Apache Http Server2.0A5: all versions
• Apache Http Server2.0A6: all versions
• Apache Http Server2.0A7: all versions
• Apache Http Server2.0A8: all versions
• Apache Http Server2.0A9: all versions

References

• http://rhn.redhat.com/errata/RHSA-2012-0128.html
• http://svn.apache.org/viewvc?view=revision&revision=1188745
• http://www.debian.org/security/2012/dsa-2405
• https://bugzilla.redhat.com/show_bug.cgi?id=752080
• http://rhn.redhat.com/errata/RHSA-2012-0128.html
• http://svn.apache.org/viewvc?view=revision&revision=1188745
• http://www.debian.org/security/2012/dsa-2405
• https://bugzilla.redhat.com/show_bug.cgi?id=752080

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