VULNERABILITY INTELLIGENCE
CVE-2011-3639
CVSS score4.3 MEDIUM
EPSS probability50.60%
CISA KEVNot currently listed
Published2011-11-30
Last modified2026-06-16
CVSS vectorAV:N/AC:M/Au:N/C:N/I:P/A:N
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 classification
- CWE-20: Improper Input Validation