What’s Vulnerable › Vulnerabilities
CVE-2026-12245: Denial of DNS over TLS service by any DoT client
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.5% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-06-25 · updated 2026-10-25
- Weakness: CWE-416
Description
NSD from version 4.13.0 has a heap use-after-free bug in logging errors on TLS connections, causing a crash of the server process, which can be triggered trivially by sending a DNS query over a DoT connection, and closing the connection without reading the response.
Affected products
- NLnet Labs NSD: from 4.13.0 before 4.14.3 — fixed in 4.14.3
How to fix
Upgrade to a fixed version: NLnet Labs NSD 4.14.3. Check the vendor advisory for mitigations.
References
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