{"id":"CVE-2026-63385","aliases":["GHSA-jcwh-pvf2-73p2"],"url":"https://o3.security/vulnerability/CVE-2026-63385","summary":"Libevent: HTTP header handling bugs create risk of access control bypass.","details":"Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has two HTTP parsing weaknesses in http.c. evhttp_decode_uri_internal decodes percent-encoded %00 bytes into literal NUL characters, which can cause downstream C string operations to truncate a path and bypass validation performed on a different representation. evhttp_header_is_valid_value also accepts obsolete line folding in header values containing carriage return or line feed characters, allowing a proxy and libevent to interpret headers differently and enabling header injection or access control bypass. The CRLF header acceptance is fixed in versions 2.1.13 and 2.2.2-alpha, but the reviewed patches do not clearly remediate the URI NUL-truncation condition.","published":"2026-08-20T17:55:36.214Z","modified":"2026-08-23T03:49:31.651811565Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/libevent/libevent/commit/758be0c0f69c1934ef9a84ab39e9f9e5fde2e6d0","label":"libevent/libevent@758be0c"},"references":[{"type":"WEB","url":"https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable"},{"type":"WEB","url":"https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63385.json"},{"type":"ADVISORY","url":"https://github.com/libevent/libevent/security/advisories/GHSA-jcwh-pvf2-73p2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63385"},{"type":"FIX","url":"https://github.com/libevent/libevent/commit/758be0c0f69c1934ef9a84ab39e9f9e5fde2e6d0"},{"type":"FIX","url":"https://github.com/libevent/libevent/commit/9170dd35e64714613e8d13b290587cfc28e258e2"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-23T03:49:31.651811565Z"}}