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Fencer Vulns
medium 5.3

CVE-2026-96405 json

Aggregate DNS name chained pointer decompression work leads to degradation of service.

published 2026-10-21 19 d ago modified 2026-10-29 10 d ago also EUVD-2026-107153

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits
0
none known

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.

Patch / fix

  • NLnet Labs Unbound 1.26.2
  • unbound Debian 13 1.26.2-0+deb13u1
  • unbound Debian 14 1.26.2-1

debian advisories DEBIAN-CVE-2026-96405

  • unbound openSUSE Tumbleweed 1.26.2-1.1

opensuse advisories openSUSE-SU-2026:12257-1

  • unbound Azure Linux 3.0 1.26.2-1

azure linux advisories AZL-110534

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
10 d ago

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

  • NLnet Labs Unbound

Classification

Weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.