High severity · published Jun 25, 2026
CVE-2026-12246
Out of bounds stack write with crafted APL RR
8.1
CVSS
0.4%
EPSS
No
On KEV
Description
NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NS
NSD · NLnet Labs
4.14.0 before 4.14.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-12246
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-12246
Patch
https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12246.txt
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