Auth bypass in Newsletters

CVE-2026-16264

The Newsletters WordPress plugin before 4.18.1 does not perform an ownership check on some of its subscriber management actions, and issues a management session to unauthenticated visitors on request, allowing attackers to read any subscriber's personal data and overwrite any subscriber's record including their email address.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (18.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 18.6% 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-2026-16264: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

  • Newsletters

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16264?
CVE-2026-16264 is a medium-severity vulnerability in Newsletters, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-09-23.
How severe is CVE-2026-16264?
Medium severity. CVSS v3 base score is 6.5 out of 10.