{"schemaVersion":3,"id":"CVE-2011-3639","aliases":["DEBIAN-CVE-2011-3639"],"status":"published","duplicateOf":null,"title":null,"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.","dates":{"published":"2011-11-30T02:00:00.000Z","modified":"2024-08-06T23:37:48.644Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":4.3,"severity":"medium","version":"2.0","versionLabel":"v2.0","source":"NVD","vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":4.3,"severity":"medium","vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.50604,"percentile":0.98907,"severity":"critical","asOf":"2026-10-18T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-18T00:00:00.000Z","baselineScore":0.50604},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.50604,"percentile":0.98907}],"last30":[{"date":"2026-09-18T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.50604,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.50604,"perce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