{"cve":"CVE-2026-63380","nvd":{"published":"2026-08-20T18:16:35.357","modified":"2026-10-26T10:10:00.140","status":"Awaiting Analysis","description":"Libevent is an event notification library. Prior to 2.2.2-alpha, libevent can dereference invalid list pointers in ws.c when evws_new_session enters its error path after evhttp_start_ws_ succeeds but bufferevent_enable_locking_ fails. evws_connection_free sees a non-null http_server and unconditionally calls TAILQ_REMOVE even though the session was never inserted into http_server->ws_sessions. A local caller able to induce this allocation or locking failure can crash the process. This issue is fixed in version 2.2.2-alpha.","cvss_v4":{"vector":"CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":5.7},"cvss_v3":null,"cwes":["CWE-416","CWE-476"],"references":["https://github.com/libevent/libevent/commit/825c18bd99f556b59d61200523237f264d5cc734","https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha","https://github.com/libevent/libevent/security/advisories/GHSA-3rpf-frgx-xq34","https://github.com/libevent/libevent/security/advisories/GHSA-3rpf-frgx-xq34"],"products":[],"source":"nvd","synced_at":"2026-10-26T10:28:23.151169805+00:00"},"epss":{"cve":"CVE-2026-63380","score":0.0014,"percentile":0.03341,"date":"2026-10-25"},"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."]}