CVE-2026-33630 (GCVE-0-2026-33630)

Vulnerability from cvelistv5 – Published: 2026-09-03 18:42 – Updated: 2026-09-05 02:00
VLAI
Title
c-ares : Use-after-free / double-free in c-ares query-completion handling, remotely triggerable via ares_getaddrinfo() over TCP
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-05 02:00 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7939 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
c-ares c-ares Affected: >= 1.32.3, < 1.34.7
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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