CVE-2026-17520: Unknown Newsletters

Medium severity, CVSS 4.8. EPSS: 0.1% chance of exploitation in the next 30 days.

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.

Affected products

• Unknown Newsletters: before 4.17 (fixed in 4.17)

Published 2026-08-29. Last modified 2026-08-31.