The Meow Gallery plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Attachment…

Why it is Yellow

• CVSS 6.4 medium

References

• https://plugins.trac.wordpress.org/browser/meow-gallery/tags/5.4.5/classes/core.php#L465
• https://plugins.trac.wordpress.org/browser/meow-gallery/tags/5.4.5/classes/core.php#L469
• https://plugins.trac.wordpress.org/browser/meow-gallery/tags/5.4.5/classes/run.php#L12
• https://plugins.trac.wordpress.org/browser/meow-gallery/tags/5.4.9/classes/core.php#L465
• https://plugins.trac.wordpress.org/browser/meow-gallery/tags/5.4.9/classes/core.php#L469
• https://plugins.trac.wordpress.org/browser/meow-gallery/tags/5.4.9/classes/run.php#L12
• https://plugins.trac.wordpress.org/changeset?old_path=/meow-gallery/tags/5.5.1&new_path=/meow-gallery/tags/5.5.2
• https://www.wordfence.com/threat-intel/vulnerabilities/id/49afa739-83f0-4ad7-9e5e-d600f293b938?source=cve

Original description

The Meow Gallery plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Attachment Alt Text (aria-label attribute) in all versions up to, and including, 5.5.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The vulnerable code path is only reachable when a gallery item is rendered as a link (i.e., link_href is non-empty), and exploitation relies on the fact that WordPress's sanitize_text_field() strips angle-bracketed tags but preserves double quotes, allowing an attacker to break out of the aria-label attribute context and inject event-handler attributes such as onclick.