CVE-2026-12244 (GCVE-0-2026-12244)
Vulnerability from cvelistv5 – Published: 2026-06-25 05:24 – Updated: 2026-06-25 12:45
VLAI
EPSS
VEX
Title
Heap overflow and crash with crafted SVCB RR
Summary
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
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-25 12:45 UTC
Assigner
NLnet Labs
CNA
References
1 reference
| URL | Tags |
|---|---|
| https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-1… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| NLnet Labs | NSD |
Affected:
4.14.0 , < 4.14.3
(semver)
|
guessed |
Date Public
2026-06-25 00:00
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