Description
WordPress is prone to multiple vulnerabilities, including cross-site scripting and prototype pollution vulnerabilities. Exploiting these issues could allow an attacker to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site, allowing the attacker to steal cookie-based authentication credentials, or to inject key/value �properties� into JavaScript objects, potentially allowing for execution of arbitrary JavaScript in a user�s session if they can trick that user into clicking a link. WordPress versions 5.9.x ranging from 5.9 and up to (and including) 5.9.1 are vulnerable.
Remediation
Update to WordPress version 5.9.2 or latest
References
https://github.com/BlackFan/client-side-prototype-pollution/blob/master/pp/jquery-query-object.md
https://github.com/WordPress/gutenberg/pull/39365/files
https://wordpress.org/news/2022/03/wordpress-5-9-2-security-maintenance-release/
Related Vulnerabilities
WordPress Plugin Floating Cart for WooCommerce Security Bypass (1.2.2)
WordPress Plugin Popup Maker-Popup for opt-ins, lead gen, & more Cross-Site Scripting (1.16.10)
Craft CMS Improper Control of Generation of Code ('Code Injection') Vulnerability (CVE-2025-23209)
MongoDb Improper Input Validation Vulnerability (CVE-2018-20804)
WordPress Plugin Gallery by BestWebSoft Cross-Site Scripting (4.4.9)