CVE-2026-1300: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in mehtevas Responsive Header Plugin
The Responsive Header plugin for WordPress is vulnerable to Stored Cross-Site Scripting via multiple plugin settings parameters in all versions up to, and including, 1.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.
AI Analysis
Technical Summary
CVE-2026-1300 is a stored cross-site scripting vulnerability (CWE-79) in the mehtevas Responsive Header WordPress plugin. The flaw exists due to improper neutralization of input during web page generation, allowing authenticated administrators to inject malicious scripts via multiple plugin settings parameters. These scripts execute in the context of users visiting the injected pages. The vulnerability affects all plugin versions up to 1.0 and only impacts multi-site WordPress installations or those with unfiltered_html capability disabled. The CVSS 3.1 base score is 4.4, reflecting a medium severity with network attack vector, high attack complexity, and requiring high privileges but no user interaction.
Potential Impact
An attacker with administrator-level access on a multi-site WordPress installation or where unfiltered_html is disabled can inject persistent malicious scripts into pages generated by the Responsive Header plugin. These scripts execute in the browsers of users who visit the injected pages, potentially leading to session hijacking, defacement, or other script-based attacks. The impact is limited by the requirement for high privileges and the specific WordPress configuration conditions.
Mitigation Recommendations
No official patch or fix is currently available for this vulnerability. Administrators should review plugin usage in multi-site environments and consider restricting administrator access to trusted users only. Monitor the vendor's advisory channels for updates regarding patches or mitigations. Since this vulnerability requires administrator privileges and specific WordPress configurations, limiting administrative access and carefully managing multi-site installations can reduce risk. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
CVE-2026-1300: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in mehtevas Responsive Header Plugin
Description
The Responsive Header plugin for WordPress is vulnerable to Stored Cross-Site Scripting via multiple plugin settings parameters in all versions up to, and including, 1.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-1300 is a stored cross-site scripting vulnerability (CWE-79) in the mehtevas Responsive Header WordPress plugin. The flaw exists due to improper neutralization of input during web page generation, allowing authenticated administrators to inject malicious scripts via multiple plugin settings parameters. These scripts execute in the context of users visiting the injected pages. The vulnerability affects all plugin versions up to 1.0 and only impacts multi-site WordPress installations or those with unfiltered_html capability disabled. The CVSS 3.1 base score is 4.4, reflecting a medium severity with network attack vector, high attack complexity, and requiring high privileges but no user interaction.
Potential Impact
An attacker with administrator-level access on a multi-site WordPress installation or where unfiltered_html is disabled can inject persistent malicious scripts into pages generated by the Responsive Header plugin. These scripts execute in the browsers of users who visit the injected pages, potentially leading to session hijacking, defacement, or other script-based attacks. The impact is limited by the requirement for high privileges and the specific WordPress configuration conditions.
Mitigation Recommendations
No official patch or fix is currently available for this vulnerability. Administrators should review plugin usage in multi-site environments and consider restricting administrator access to trusted users only. Monitor the vendor's advisory channels for updates regarding patches or mitigations. Since this vulnerability requires administrator privileges and specific WordPress configurations, limiting administrative access and carefully managing multi-site installations can reduce risk. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Wordfence
- Date Reserved
- 2026-01-21T18:44:21.554Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69748ef84623b1157cac2e8a
Added to database: 1/24/2026, 9:20:56 AM
Last enriched: 4/9/2026, 9:56:46 PM
Last updated: 5/8/2026, 3:28:49 PM
Views: 142
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