CVE-2026-12244

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

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12244.txt	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:*

History

26 Jun 2026, 02:07

Type	Values Removed	Values Added
CPE		cpe:2.3:a:nlnetlabs:nsd::::::::
References	~~() https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12244.txt -~~	() https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12244.txt - Patch, Vendor Advisory
First Time		Nlnetlabs Nlnetlabs nsd
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.8

25 Jun 2026, 07:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 07:16

Updated : 2026-06-26 02:07

NVD link : CVE-2026-12244

Mitre link : CVE-2026-12244

CVE.ORG link : CVE-2026-12244

JSON object : View

Products Affected

nlnetlabs

nsd

CWE

CWE-122

Heap-based Buffer Overflow

CWE-190

Integer Overflow or Wraparound

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