CVE-2026-101338 (GCVE-0-2026-101338)

Vulnerability from cvelistv5 – Published: 2026-10-14 10:56 – Updated: 2026-10-14 14:09
VLAI
Title
Stack overwrite from a specially crafted and formatted SVCB or HTTPS RR
Summary
When a SVCB or HTTPS RR has filled the wire format RDATA up to the brim, another ECH parameter may overwrite the stack, and once beyond the limit, the base64 decoder can write attacker controlled data of unlimited size. Zone files which are written out by NSD itself, such as 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).
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-14 14:09 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
NLnet Labs CNA
CNA scorecard B 82/100 over 61 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NLnet Labs NSD Affected: 4.10.0 , < 4.15.3 (semver)
guessed Create a notification for this product.
Date Public
2026-10-14 12:00
Credits
Qifan Zhang from Palo Alto Networks
Show details on NVD website
To clipboard 

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