CVE-2026-12969

Public on 2026-06-23
Modified on 2026-06-25
Description
An out-of-bounds read vulnerability exists in dnsmasq's find_soa() function in src/rfc1035.c. When parsing NS section records, extract_name() is called with extrabytes=0, failing to validate that 10 additional bytes exist for fixed-length DNS record fields. A remote attacker controlling a DNS zone can exploit this via a crafted NXDOMAIN response to cause a 10-byte heap out-of-bounds read, potentially accessing stale data from prior transactions.
Severity
Medium severity
Medium
See what this means
CVSS v3 Base Score
5.3
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 2 - Core dnsmasq Not Affected
Amazon Linux 2 - Dnsmasq Extra dnsmasq Not Affected
Amazon Linux 2 - Dnsmasq2.85 Extra dnsmasq No Fix Planned
Amazon Linux 2023 dnsmasq Not Affected

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N