CVE-2026-96405 (GCVE-0-2026-96405)

Vulnerability from cvelistv5 – Published: 2026-10-21 08:57 – Updated: 2026-10-29 19:07
VLAI
Title
Aggregate DNS name chained pointer decompression work leads to degradation of service.
Summary
NLnet Labs Unbound up to and including version 1.26.1 limits compression-pointer traversal for each individual domain-name operation but has no aggregate inbound decompression-work budget. Many chained compression pointers in a message results in a lot of CPU usage following them. A malicious actor with recursive-query access and control of an ordinarily delegated authority that serves specially crafted replies can exploit the vulnerability and degrade Unbound's general performance.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-29 19:07 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
NLnet Labs CNA
CNA scorecard B 82/100 over 76 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NLnet Labs Unbound Affected: 0 , < 1.26.2 (semver)
guessed Create a notification for this product.
Date Public
2026-10-21 00:00
Credits
Yuheng Zhang (Tsinghua University & Jingxian Technology Co., Ltd.) Jianjun Chen (Tsinghua University) Zihan Wang (Z.AI Co., Ltd.) Kaiwen Shen (CloudItera)
Show details on NVD website
To clipboard 

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