CVE-2011-4317

Severity: medium (CVSS 4.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 59.6% 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 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21, 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 via a malformed URI containing an @ (at sign) character and a : (colon) character in invalid positions. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-3368.

Affected products

Apache HTTP Server: 1.3, 1.3.0, 1.3.1, 1.3.1.1, 1.3.2, 1.3.3 (+94)

References

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