5.3

CVE-2026-96405: nlnet labs unbound

CVSS: 5.3v3.1MediumReceived
AliasesDEBIAN-CVE-2026-96405
Published 21-10-2026Last modified 21-10-2026
Open JSON

Vulnerability summary

CVE-2026-96405 is a medium (CVSS 5.3) vulnerability in nlnet labs unbound. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 13.9% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.24%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 21-10-2026
    PublishedVulnerability first disclosed.

Description

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.24%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

21-10-202621-10-2026
EPSS score
0.24%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • unboundAll versions (No fix recorded)
Nlnet labs1 product

2 vendors · 2 products

References

2 links