{"id":"CVE-2026-12244","details":"If NSD is configured as secondary for a zone, the primary of that zone can crash NSD with an AXFR containing a DNS message with a special crafted SVCB RR with an rdata size of 65512, that let's an (uint16_t) variable that is used to allocate space needed for the RR wrap (because total size \u003e 65535), causing a heap overflow. The attacker can perform a controlled (RCE class) head write of up to 65509 bytes","modified":"2026-07-15T06:21:52.850500Z","published":"2026-06-25T07:16:44.900Z","references":[{"type":"FIX","url":"https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12244.txt"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/nlnetlabs/nsd","events":[{"introduced":"5c760d0f00e282e1626cbadfc67e8bb11744f20b"},{"fixed":"fc930b88cb4f628defae9835449065945bda7ddc"}],"database_specific":{"cpe":"cpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"4.14.0"},{"fixed":"4.14.3"}],"source":"CPE_RANGE"}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-12244.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}