VULNERABILITY INTELLIGENCE

CVE-2026-33630

CVSS score7.5 HIGH
EPSS probability0.84%
CISA KEVNot currently listed
Published2026-09-03
Last modified2026-09-09
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

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.

Weakness classification

  • security-advisories@github.com: CWE-415

Primary references