Stored XSS via nonce-free settings update
Published Apr 22, 2026 · Updated Apr 22, 2026
Cross-site request forgery in WP Responsive Popup + Optin 1.4 and earlier allows remote attackers to overwrite plugin settings. The settings handler in wpo_admin_page.php accepts changes without generating or verifying a WordPress nonce and stores attacker-controlled wpo_image_url input that is later rendered. Exploitation requires an authenticated administrator to submit the forged request, enabling stored script execution when the image URL is displayed.
Summary
What happened
Cross-site request forgery in WP Responsive Popup + Optin 1.4 and earlier allows remote attackers to overwrite plugin settings. The settings handler in wpo_admin_page.php accepts changes without generating or verifying a WordPress nonce and stores attacker-controlled wpo_image_url input that is later rendered. Exploitation requires an authenticated administrator to submit the forged request, enabling stored script execution when the image URL is displayed.
The record
- CVE
- CVE-2026-4131
- Published
- Apr 22, 2026
- Updated
- Apr 22, 2026
- Vendor
- sphex1987
- Product
- WP Responsive Popup + Optin
- Classifications
- CWE-352, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 22, 2026CVE publishedPublication date reported by the CVE source.
- Apr 22, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=0 <=1.4
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What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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