{"schemaVersion":3,"id":"CVE-2026-63385","aliases":["RHSA-2026:70254","UBUNTU-CVE-2026-63385","DEBIAN-CVE-2026-63385"],"status":"published","duplicateOf":null,"title":null,"description":"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.","dates":{"published":"2026-08-20T17:55:36.214Z","modified":"2026-08-21T21:46:26.752Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.2,"severity":"critical","version":"4.0","versionLabel":"v4.0","source":"CVE.org","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:L/SI:L/SA:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"4.0","versionLabel":"v4.0","source":"CVE.org","score":9.2,"severity":"critical","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:L/SI:L/SA:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Red 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