CVE-2026-6742 in Advanced iFrame Plugin
Summary
by MITRE • 07/08/2026
The Advanced iFrame plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'additional' parameter in all versions up to, and including, 2026.1 due to insufficient input sanitization and output escaping. 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.
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Analysis
by VulDB Data Team • 07/08/2026
The Advanced iFrame plugin for WordPress represents a critical security vulnerability through its stored cross-site scripting flaw in versions up to and including 2026.1. This vulnerability stems from inadequate input sanitization and output escaping mechanisms within the plugin's handling of the 'additional' parameter, creating a persistent security risk that can be exploited by attackers with contributor-level privileges or higher. The flaw exists in the plugin's core functionality where user-supplied data is not properly validated or escaped before being rendered in web pages, allowing malicious scripts to be stored and executed in the context of other users' browsers.
The technical nature of this vulnerability places it firmly within the CWE-79 category of Cross-Site Scripting, specifically classified as a stored XSS variant where malicious payloads are permanently saved on the server and executed whenever affected pages are accessed. Attackers can leverage this weakness to inject arbitrary web scripts that execute in the context of other users' browsers, potentially enabling session hijacking, data theft, or further compromise of the WordPress installation. The vulnerability's exploitation requires only contributor-level access, making it particularly dangerous as it can be triggered by users who should normally have limited privileges within the WordPress administrative interface.
The operational impact of this vulnerability extends beyond simple script execution to create a persistent threat vector that can compromise multiple users simultaneously. When authenticated attackers inject malicious scripts through the 'additional' parameter, these payloads become part of the plugin's stored content and execute whenever any user accesses pages containing the injected content. This creates a chain reaction where compromised users inadvertently propagate the malicious code to other visitors, effectively turning each compromised user into a vector for further attacks. The low privilege requirement means that even less privileged contributors can potentially cause significant damage to the entire WordPress installation.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security hardening measures. The most critical step involves updating to the latest version of the Advanced iFrame plugin where the input sanitization and output escaping have been properly implemented to prevent XSS injection. Administrators should also implement additional security measures including regular security audits, input validation on all user-supplied parameters, and monitoring for suspicious activity within contributor accounts. Network-level protections such as web application firewalls can provide additional layers of defense by detecting and blocking malicious script injections before they can be executed. The vulnerability highlights the importance of proper security practices in plugin development and emphasizes the need for regular security assessments of third-party WordPress components to prevent similar issues from occurring in the future.
This vulnerability demonstrates how seemingly minor input validation gaps can create significant security risks in content management systems, particularly when malicious actors can leverage existing user privileges to compromise the entire platform. The combination of contributor-level access requirements with persistent script execution capabilities makes this attack vector particularly dangerous for WordPress installations that do not maintain strict access controls or regular security updates. Organizations should treat such vulnerabilities as critical incidents requiring immediate attention and comprehensive security reviews to prevent exploitation and ensure the integrity of their web applications.