{"id":"CVE-2013-4366","aliases":["GHSA-pqwh-44jj-p5rm"],"url":"https://o3.security/vulnerability/CVE-2013-4366","summary":"Hostname verification in Apache HttpClient 4.3 was disabled by default","details":"http/impl/client/HttpClientBuilder.java in Apache HttpClient 4.3.x before 4.3.1 does not ensure that X509HostnameVerifier is not null, which allows attackers to have unspecified impact via vectors involving hostname verification.","published":"2017-10-30T19:29:00Z","modified":"2026-04-10T03:44:30.197869Z","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"org.apache.httpcomponents:httpclient","fixedVersion":"4.3.1"}],"fix":null,"references":[{"type":"ADVISORY","url":"http://svn.apache.org/r1528614"},{"type":"ADVISORY","url":"http://www.apache.org/dist/httpcomponents/httpclient/RELEASE_NOTES-4.3.x.txt"},{"type":"FIX","url":"http://svn.apache.org/r1528614"},{"type":"REPORT","url":"http://svn.apache.org/r1528614"},{"type":"REPORT","url":"http://www.apache.org/dist/httpcomponents/httpclient/RELEASE_NOTES-4.3.x.txt"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-04-10T03:44:30.197869Z"}}