What is CVE-2026-17520?

CVE-2026-17520 is a medium-severity vulnerability in Newsletters, classified under Inadequate Encryption Strength. CVSS score: 4.8/10. Published 2026-08-29.

How severe is CVE-2026-17520?

Medium severity. CVSS v3 base score is 4.8 out of 10.

Vulnerability in Newsletters

CVE-2026-17520

The Newsletters WordPress plugin before 4.17 does not generate its API key using a sufficiently random source, deriving it from a publicly known value, allowing unauthenticated attackers to compute the key and perform privileged actions such as adding and deleting subscribers and sending emails, when the optional API has been enabled.

Published 2026-08-29 · last modified 2026-08-31.

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: 0.001 (1.7th percentile), scored 2026-10-14.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 1.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000

Affected products

Newsletters

Weakness classification (CWE)

CWE-326 — Inadequate Encryption Strength

References

wpscan.com/vulnerability/5a719e6b-22e1-4950-bf17-cd92e2ea6685/ (technical-description, exploit, vdb-entry)

Frequently asked questions

What is CVE-2026-17520?: CVE-2026-17520 is a medium-severity vulnerability in Newsletters, classified under Inadequate Encryption Strength. CVSS score: 4.8/10. Published 2026-08-29.
How severe is CVE-2026-17520?: Medium severity. CVSS v3 base score is 4.8 out of 10.