What is CVE-2026-42396?

CVE-2026-42396 is a medium-severity vulnerability in Powerdns Authoritative, classified under Code Injection. CVSS score: 4.9/10. Published 2026-05-21.

How severe is CVE-2026-42396?

Medium severity. CVSS v3 base score is 4.9 out of 10.

RCE in Powerdns Authoritative

CVE-2026-42396

Insufficient Validation of Member Zone Data May Cause Catalog Zone Transfer to Fail

Vulnerability class: RCE (Remote Code Execution)

Published 2026-05-21 · last modified 2026-07-23.

CVSS v3 metric

CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.008 (54.0th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 54th percentile — 54.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.008 · change: +0.004

Affected products

Powerdns Authoritative — versions 4.9.0, 5.0.0

Weakness classification (CWE)

CWE-94 — Code Injection

References

docs.powerdns.com/authoritative/security-advisories/powerdns-advisory-powerdns-… (Broken Link)

Frequently asked questions

What is CVE-2026-42396?: CVE-2026-42396 is a medium-severity vulnerability in Powerdns Authoritative, classified under Code Injection. CVSS score: 4.9/10. Published 2026-05-21.
How severe is CVE-2026-42396?: Medium severity. CVSS v3 base score is 4.9 out of 10.