{"cve":"CVE-2011-3639","nvd":{"published":"2011-11-30T04:05:58.437","modified":"2026-06-16T23:33:40.360","status":"Modified","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.","cvss_v4":null,"cvss_v3":null,"cwes":["CWE-20"],"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"],"products":["apache:http_server","apache:http_server2.0a1","apache:http_server2.0a2","apache:http_server2.0a3","apache:http_server2.0a4","apache:http_server2.0a5","apache:http_server2.0a6","apache:http_server2.0a7","apache:http_server2.0a8","apache:http_server2.0a9"],"source":"nvd","synced_at":"2026-10-19T19:59:31.623151214+00:00"},"epss":{"cve":"CVE-2011-3639","score":0.49697,"percentile":0.98895,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}