CVE-2026-86824mediumCWE-326

CVE-2026-86824: medium-severity vulnerability in Newsletter

Newsletter < 9.3.8 - Unauthenticated Subscriber PII Disclosure and Modification via Predictable Tracking Signature Key

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 4.8epss 0.2%
The Newsletter WordPress plugin before 9.3.8 does not generate its email tracking signing key with sufficient entropy and signs its tracking links with an unkeyed hash, allowing an unauthenticated attacker who recovers that key offline to forge tracking links, obtain any subscriber's session token, and read and modify that subscriber's stored personal data.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Affected products
Unknown · Newsletter
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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