CVE-2026-12244 — Heap overflow and crash with crafted SVCB RR

CVE-2026-12244

Heap overflow and crash with crafted SVCB RR PUBLISHED

Description (CNA)

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 > 65535), causing a heap overflow. The attacker can perform a controlled (RCE class) head write of up to 65509 bytes

Affected (CNA)

Vendor / product	Versions
NLnet Labs / NSD	affected 4.14.0 before 4.14.3

CWE

CWE-190, CWE-122

References

https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12244.txt

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.