CVE-2026-39155 (GCVE-0-2026-39155)

Vulnerability from cvelistv5 – Published: 2026-07-23 00:00 – Updated: 2026-07-24 19:35
VLAI
Summary
Knot DNS before 3.4.10 and 3.5.x before 3.5.4 contains a vulnerability in mod-onlinesign where the next NSEC owner name can be computed incorrectly. This can create an overly broad authenticated denial interval, allowing downstream validating resolvers using aggressive negative caching to synthesize negative answers for legitimate names and causing resolver-side denial of service.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-24 19:35 UTC
CWE
  • n/a
  • CWE-345 - Insufficient Verification of Data Authenticity
Assigner
mitre CNA under the mitre root
CNA scorecard E 28/100 over 2324 records in the last 180 days details
References
Show details on NVD website
To clipboard 

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