CVE-2026-101341
NSD: Stack overwrite from specially formatted TXT-DATA RDATA field
NLnet Labs NSD
CVSS
8.7HighExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.34%Chance of exploitation activity in the next 30 days, higher than 25% of CVEs. Scored 23 Oct 2026FIRST EPSS
What fixes it
- 4.15.3NSDCVE List
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Description
Tokens of text in RDATA (of for example TXT records) under 32 bytes are not checked to stay within the space reserved for the RDATA allowing for arbitrary sized out of bound stack writes, including an overwrite of a callback function pointer which is called directly after parse. Zone files which are written out by NSD itself, such for zones for which the NSD instance is secondary, will not be formatted like this. The zone file must be fed to NSD directly, (but it could come, for example, from an operator controlled provisioning system).
Text from CVE List
Affected versions 1
- NSDaffected: 4.10.0 before 4.15.3CVE List