CVE-2025-11876: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in jbrinley Mailgun Subscriptions
The Mailgun Subscriptions plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'mailgun_subscription_form' shortcode in all versions up to, and including, 1.3.1 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
AI Analysis
Technical Summary
CVE-2025-11876 is a stored cross-site scripting vulnerability (CWE-79) in the Mailgun Subscriptions plugin for WordPress, affecting all versions up to and including 1.3.1. The issue stems from inadequate input sanitization and output escaping on user-supplied attributes in the 'mailgun_subscription_form' shortcode. Authenticated attackers with contributor-level privileges or higher can inject arbitrary JavaScript code that executes in the context of users visiting the compromised pages. This vulnerability can lead to limited confidentiality and integrity impacts, as indicated by the CVSS vector (AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N).
Potential Impact
Successful exploitation allows authenticated users with contributor or higher privileges to inject and execute arbitrary scripts in the context of other users viewing the affected pages. This can lead to partial confidentiality and integrity loss, such as session hijacking or content manipulation. There is no impact on availability. No known exploits in the wild have been reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict contributor-level access to trusted users only and consider disabling or removing the Mailgun Subscriptions plugin if possible. Monitor for plugin updates from the vendor addressing this vulnerability.
CVE-2025-11876: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in jbrinley Mailgun Subscriptions
Description
The Mailgun Subscriptions plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'mailgun_subscription_form' shortcode in all versions up to, and including, 1.3.1 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-11876 is a stored cross-site scripting vulnerability (CWE-79) in the Mailgun Subscriptions plugin for WordPress, affecting all versions up to and including 1.3.1. The issue stems from inadequate input sanitization and output escaping on user-supplied attributes in the 'mailgun_subscription_form' shortcode. Authenticated attackers with contributor-level privileges or higher can inject arbitrary JavaScript code that executes in the context of users visiting the compromised pages. This vulnerability can lead to limited confidentiality and integrity impacts, as indicated by the CVSS vector (AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N).
Potential Impact
Successful exploitation allows authenticated users with contributor or higher privileges to inject and execute arbitrary scripts in the context of other users viewing the affected pages. This can lead to partial confidentiality and integrity loss, such as session hijacking or content manipulation. There is no impact on availability. No known exploits in the wild have been reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict contributor-level access to trusted users only and consider disabling or removing the Mailgun Subscriptions plugin if possible. Monitor for plugin updates from the vendor addressing this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Wordfence
- Date Reserved
- 2025-10-16T16:35:35.329Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 693bc3e35f3fdafda42e6cd6
Added to database: 12/12/2025, 7:27:31 AM
Last enriched: 4/9/2026, 8:54:30 PM
Last updated: 5/8/2026, 8:54:11 PM
Views: 134
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