CVE-2026-86824: Newsletter < 9.3.8 - Unauthenticated Subscriber PII Disclosure and Modification via Predictable Tracking Signature Key

Description

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 vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

Attack vector

Network

Complexity

High

Privileges

None

User interaction

None

Confidentiality

Low

Integrity

Low

Availability

None

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.2% · higher than 4% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

NE

Newsletter ·

before 9.3.8 · source: vendor