8.2

CVE-2026-19401: nlnet labs nsd Uncontrolled Resource Consumption

CVSS: 8.2v4.0HighAnalyzed
AliasesUBUNTU-CVE-2026-19401DEBIAN-CVE-2026-19401
Published 26-08-2026Last modified 26-08-2026
Open JSON

Vulnerability summary

CVE-2026-19401 is a high (CVSS 8.2) Uncontrolled Resource Consumption vulnerability in nlnet labs nsd. EPSS estimates a 0.28% chance of exploitation in the next 30 days, higher than 19.1% of scored vulnerabilities.

Overall risk
33/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.2/10
010
High · v4.0 (CVE.org)
EPSS score
0.28%
0%100%
Low · -0.08 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 26-08-2026
    PublishedVulnerability first disclosed.
  2. 26-08-2026
    Last modifiedVulnerability information updated.

Description

Any remote client can crash a (debugging/non-release build type) NSD serve child by sending it a special crafted message with a specially tuned number of DNS Cookie options (17 when UDP payload size is 512). By continuously crashing the serve childs, the remote client can severely hamper or, when positioned sufficiently close, deny all DNS service.

CVSS metrics

6 scores · 4 sources · 2 versions

EPSS trend

Probability

0.28%

Chance of exploitation in the next 30 days

Percentile

19%

Versus all other CVEs

30-day change

-0.08 pp

From 0.36% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.28%

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
  • nsdAll versions (No fix recorded) | < 4.15.1-1
Nlnet labs1 product
  • nsd≥ 4.3.7, < 4.15.1
Nlnetlabs1 product
  • nsd≥ 4.3.7, < 4.15.1
Ubuntu1 product
  • nsdAll versions (No fix recorded)

4 vendors · 4 products

References

4 links