CVE-2026-4131 Cross-site request forgery in WP Responsive Popup + Optin
Attackers can trick admins into updating plugin settings, enabling stored XSS via image URL parameter due to missing CSRF protection.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-4131?
CVE-2026-4131 is a medium-severity vulnerability in sphex1987 WP Responsive Popup + Optin, published on 22 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The WP Responsive Popup + Optin plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to and including 1.4. This is due to the settings form on the admin page (wpo_admin_page.php) lacking nonce generation (wp_nonce_field) and verification (wp_verify_nonce/check_admin_referer). This makes it possible for unauthenticated attackers to update all plugin settings including the 'wpo_image_url' parameter via a forged request, granted they can trick a site administrator into performing an action such as clicking a link.
Weakness: CWE-352
Which versions are affected by CVE-2026-4131?
How do I fix CVE-2026-4131?
No fix has been published for CVE-2026-4131 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-4131 being exploited?
There is no known exploitation of CVE-2026-4131 in the wild and no public exploit code.
Sources
Also known as GHSA-mjqc-rj22-4rf2.