CVE-2026-33630 (GCVE-0-2026-33630)
Vulnerability from cvelistv5
Published
2026-09-03 18:42
Modified
2026-09-05 02:00
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
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 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.
References
Impacted products
Vendor Product Version
c-ares c-ares Version: >= 1.32.3, < 1.34.7
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