CVE-2026-4131

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.

Published: 2026-04-22 Last update: 2026-04-22 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-4131 is rated Low Risk (24.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-4131

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-22 0.01%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-4131

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 2.7 [email protected]

Weakness enumeration for CVE-2026-4131

GitHub Security Advisory for CVE-2026-4131

GHSA-mjqc-rj22-4rf2 · Severity: medium — The WP Responsive Popup + Optin plugin for WordPress is vulnerable to Cross-Site Request Forgery...

Affected software / configurations for CVE-2026-4131

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-4131

URL Tags
https://plugins.trac.wordpress.org/browser/wp-popup-optin/tags/1.4/wp-popup-optin.php#L218
https://plugins.trac.wordpress.org/browser/wp-popup-optin/tags/1.4/wpo_admin_page.php#L103
https://plugins.trac.wordpress.org/browser/wp-popup-optin/tags/1.4/wpo_admin_page.php#L104
https://plugins.trac.wordpress.org/browser/wp-popup-optin/tags/1.4/wpo_admin_page.php#L15
https://plugins.trac.wordpress.org/browser/wp-popup-optin/tags/1.4/wpo_admin_page.php#L43
https://plugins.trac.wordpress.org/browser/wp-popup-optin/trunk/wp-popup-optin.php#L218
https://plugins.trac.wordpress.org/browser/wp-popup-optin/trunk/wpo_admin_page.php#L103
https://plugins.trac.wordpress.org/browser/wp-popup-optin/trunk/wpo_admin_page.php#L104
https://plugins.trac.wordpress.org/browser/wp-popup-optin/trunk/wpo_admin_page.php#L15
https://plugins.trac.wordpress.org/browser/wp-popup-optin/trunk/wpo_admin_page.php#L43
https://www.wordfence.com/threat-intel/vulnerabilities/id/0a8a49c4-21e8-447c-94da-8241c7d66c29?source=cve
cvelogic Threat Intelligence