CVE-2026-69184: falha de alta gravidade em c-ares
c-ares: CPU-exhaustion denial of service via unbounded DNS name compression pointer chains
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21Vexday Risk Score
Sem sinal de exploração. Nenhum artefato público de exploração conhecido até agora.
ssvc Trackcvss 7.5epss 0.5%
c-ares is an asynchronous resolver library. Prior to 1.34.7, ares_dns_name_parse() enforces backward DNS compression pointers but does not bound the total pointer hops or assembled name length. A malicious DNS server can send a response containing a long descending pointer chain and many resource records whose NAME or RDATA fields refer to the chain, causing repeated decompression work that grows quadratically with message size. A single crafted response can stall the single-threaded c-ares event loop and deny DNS resolution, without causing memory corruption or information disclosure. This issue is fixed in version 1.34.7.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Produtos afetados
c-ares · c-aresCVEs relacionadas — c-ares
No mesmo produto, das mais perigosas para as menos.
CVE-2023-32067HIGH0-byte UDP payload DoS in c-aresEPSS 1.6%CVE-2023-31124LOWAutoTools does not set CARES_RANDOM_FILE during cross compilationEPSS 0.9%CVE-2023-31147MEDIUMInsufficient randomness in generation of DNS query IDs in c-aresEPSS 0.9%CVE-2026-33630HIGHc-ares : Use-after-free / double-free in c-ares query-completion handling, remotely triggerable via ares_getaddrinfo() over TCPEPSS 0.8%CVE-2025-31498HIGHc-ares has a use-after-free in read_answers()EPSS 0.6%CVE-2026-69186MEDIUMc-ares: Memory-amplification denial of service via unvalidated DNS header record countsEPSS 0.5%
Referências
https://github.com/c-ares/c-ares/commit/5c8341ba6ff3a8e4e4dfd616f8ed0418838b8b7bhttps://github.com/c-ares/c-ares/commit/f1288bbc70e9a1e0a77134c2382157e52d326aeahttps://github.com/c-ares/c-ares/pull/1164https://github.com/c-ares/c-ares/pull/1210https://github.com/c-ares/c-ares/releases/tag/v1.34.7https://github.com/c-ares/c-ares/security/advisories/GHSA-pjmc-gx33-gc76