USN-8542-1: Dnsmasq vulnerabilities
Yiwei Hou discovered that Dnsmasq incorrectly handled logging of DS or DNSKEY. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2026-12725) It was discovered that Dnsmasq incorrectly validated the length of fixed-length DNS record fields when parsing NS section records. A remote attacker could possibly use this issue to cause Dnsmasq to read out of bounds, possibly exposing sensitive information. (CVE-2026-12969)
CSIRTS triage
- What
- Dnsmasq has vulnerabilities that could lead to denial of service and potential information exposure.
- Who is affected
- Users of Dnsmasq are affected by these vulnerabilities.
- Urgency
- The severity is unknown, but users should address these vulnerabilities to prevent potential issues.
- Action
- Users should apply the latest patches for Dnsmasq.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://ubuntu.com/security/notices/USN-8542-1
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-127250.40% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all scored CVEs.
- Low exploitation riskCVE-2026-129690.24% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 15% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-12725 | coverage & exploitation status | NVD · CVE.org |
| CVE-2026-12969 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- medium[UPDATE] [medium] dnsmasq: Vulnerability Allows Information Disclosurecert-bund
- medium[UPDATE] [medium] dnsmasq: Vulnerability allows Denial of Servicecert-bund
- mediumCVE-2026-12969: Dnsmasq: dnsmasq: out-of-bounds read in find_soa() due to missing extrabytes validationmsrc
- mediumCVE-2026-12725: Dnsmasq: dnsmasq: heap buffer overflow in log_query() when logging unsupported ds/dnskey repli…msrc
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