{"id":"CVE-2026-33630","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-33630","summary":"c-ares is an asynchronous resolver library. From ver 1.32.3 until 1.34.7, a use-after-free / double-free in c-ares' query-completion handling. The same flaw — a query's callback being…","details":"c-ares is an asynchronous resolver library. From ver 1.32.3 until 1.34.7, a use-after-free / double-free in c-ares' query-completion handling. The same flaw — a query's callback being invoked while the query is still linked in the channel's internal lookup structures — is present at multiple points in the resend/finish path (timeout handling, response handling, and query dispatch). If the query, or for ares_getaddrinfo() the owning host_query, is freed as a side effect of that callback, it is then accessed and/or freed a second time. This vulnerability is fixed in ver 1.34.7.","published":"2026-09-03T19:17:27.420","modified":"2026-09-03T19:17:27.420","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/c-ares/c-ares/commit/d823199b688052dcdc1646f2ab4cb8c16b1c644a","label":"c-ares/c-ares@d823199"},"references":[{"type":"WEB","url":"https://github.com/c-ares/c-ares/commit/d823199b688052dcdc1646f2ab4cb8c16b1c644a"},{"type":"WEB","url":"https://github.com/c-ares/c-ares/releases/tag/v1.34.7"},{"type":"WEB","url":"https://github.com/c-ares/c-ares/security/advisories/GHSA-6wfj-rwm7-3542"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-09-03T19:17:27.420"}}