7.5

CVE-2026-33630

Medienbericht

c-ares : Use-after-free / double-free in c-ares query-completion handling, remotely triggerable via ares_getaddrinfo() over TCP

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.
Daten sind bereitgestellt durch das CVE Programm von einer CVE Numbering Authority (CNA) (Unstrukturiert).
Herstellerc-ares
≫
Produkt c-ares
Version >= 1.32.3, < 1.34.7
Status affected
VulnDex Vulnerability Enrichment
Diese Information steht angemeldeten Benutzern zur Verfügung. Login Login
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.45% 0.378
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 7.5 3.9 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-415 Double Free

The product calls free() twice on the same memory address.

CWE-416 Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Für Zugriff zu Vulnerability Intelligence ist ein VulnDex Zugang erforderlich.
VulnDex Intel
Media Report
08.09.2026 20:38
https://github.com/c-ares/c-ares/security/advisories/GHSA-6wfj-rwm7-3542
https://github.com/c-ares/c-ares/commit/d823199b688052dcdc1646f2ab4cb8c16b1c644a
https://github.com/c-ares/c-ares/releases/tag/v1.34.7
https://github.com/c-ares/c-ares/commit/1fa3b86a0b8d18fe7b60f3228a01d770feb026bc
https://github.com/c-ares/c-ares/pull/1237