CVE-2026-69186 c-ares: Memory-amplification denial of service via unvalidated DNS header record counts

c-ares is an asynchronous resolver library. Prior to 1.34.7, aresdnsparse trusts the attacker-controlled ANCOUNT, NSCOUNT, and ARCOUNT fields before confirming that the DNS response contains enough bytes for the claimed records. Because processanswer invokes parsing before transaction ID and...

PT-2026-80176

Name of the Vulnerable Software and Affected Versions c-ares versions prior to 1.34.8-1.1 Description A memory-amplification denial of service occurs due to unvalidated DNS header record counts. This allows an attacker to cause excessive memory consumption by manipulating the record counts in DNS...