Auth bypass in Newsletters

CVE-2026-16269

The Newsletters WordPress plugin before 4.16 does not strictly compare its API authentication key, allowing unauthenticated attackers to bypass the API authentication via type juggling and perform privileged actions such as modifying subscriber records and sending emails, when the optional API has been enabled.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.004 (30.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 30.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-16269: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

  • Newsletters — versions 0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16269?
CVE-2026-16269 is a medium-severity vulnerability in Newsletters, classified under Improper Authentication. CVSS score: 4.8/10. Published 2026-08-08.
How severe is CVE-2026-16269?
Medium severity. CVSS v3 base score is 4.8 out of 10.