CVE-2026-90981
MediumCVSS 6.1Summary
The Newsletter – Send awesome emails from WordPress plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'nn' parameter in all versions up to, and including, 9.3.8 due to insufficient input sanitization and output escaping. Unauthenticated attackers can inject arbitrary web scripts if they trick a user into clicking a link.
Risk Assessment
An attacker can perform XSS against a logged-in administrator, potentially leading to session hijacking or administrative actions. Exploitation requires victim interaction (clicking a link).
Recommendation
Update the Newsletter plugin to a version later than 9.3.8. Exercise caution when clicking links in emails, even from trusted senders.
Other vulnerabilities in Newsletter
See all- CVE-2026-86823Medium
The Newsletter WordPress plugin before 9.3.7 does not validate the destination of the redirect performed after a public subscription action. Unauthenticated attackers can redirect users to arbitrary external sites and disclose a subscriber token that grants access to that subscriber record's front-end actions.
- CVE-2026-66596High
Unauthenticated Cross Site Scripting (XSS) vulnerability in Newsletter plugin versions up to 9.3.3. An attacker can inject malicious script without authentication.
Original NVD description (English source)
The Newsletter – Send awesome emails from WordPress plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'nn' parameter in all versions up to, and including, 9.3.8 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. Successful exploitation requires the victim to be a logged-in administrator, as the antibot check auto-passes for authenticated users, routing the unsanitized payload through the administrator-visible output branch of dienow().