Buffer overflow in Thekelleys Dnsmasq
CVE-2026-12725
A heap-based buffer overflow was found in dnsmasq. When DNSSEC validation and query logging are both enabled, logging of DS or DNSKEY replies containing unsupported algorithm or digest types can cause dnsmasq to write past the end of an internal logging buffer. A remote attacker able to supply such a DNS response may crash the dnsmasq process, resulting in denial of service.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (42.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-12725 (Mitigation, vdb-entry, Vendor Advisory)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-12725?
- CVE-2026-12725 is a medium-severity vulnerability in Thekelleys Dnsmasq, classified under Heap-based Buffer Overflow. CVSS score: 5.9/10. Published 2026-06-22.
- How severe is CVE-2026-12725?
- Medium severity. CVSS v3 base score is 5.9 out of 10.