CVE-2026-57366 in WPAdverts Plugin
Summary
by MITRE • 07/02/2026
Unauthenticated Cross Site Scripting (XSS) in WPAdverts <= 2.3.1 versions.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 07/02/2026
The vulnerability under examination represents an unauthenticated cross site scripting flaw affecting WPAdverts plugin versions up to and including 2.3.1. This security weakness resides within the WordPress ecosystem where malicious actors can inject arbitrary javascript code through vulnerable input parameters without requiring authentication credentials. The vulnerability stems from insufficient output sanitization and validation of user-supplied data, particularly in areas where advertisements are processed or displayed. According to CWE-79, this falls under the category of Cross Site Scripting where improperly filtered output allows attackers to execute malicious scripts in victims' browsers. The flaw manifests when unauthenticated users interact with advertisement submission forms, comment sections, or other user-facing interfaces that process external input without adequate sanitization measures.
The technical implementation of this vulnerability exploits the plugin's failure to properly escape and validate data before rendering it within web pages. Attackers can craft malicious payloads containing javascript code within advertisement content, form fields, or URL parameters that get executed when legitimate users view affected pages. The impact extends beyond simple script execution as it can lead to session hijacking, credential theft, and redirection to malicious sites. This vulnerability directly maps to ATT&CK technique T1566 which involves the use of spearphishing with malicious attachments or links to gain initial access. The lack of authentication requirements makes this particularly dangerous as any visitor to a compromised site can exploit it without needing administrative privileges or user credentials.
The operational impact of this vulnerability creates significant risk for WordPress sites utilizing WPAdverts plugin in their advertising infrastructure. When exploited, the XSS attack can compromise user sessions, steal cookies, redirect visitors to phishing sites, and potentially escalate to full system compromise if attackers gain access to other vulnerable components. The vulnerability affects not only individual user privacy but also business operations by potentially damaging brand reputation and exposing sensitive advertisement data. Organizations using this plugin may face regulatory compliance issues under data protection frameworks such as gdpr or ccpa when user data is compromised through such attacks. The widespread adoption of WPAdverts makes this vulnerability particularly concerning for the broader WordPress community.
Mitigation strategies should focus on immediate plugin updates to versions that address the XSS vulnerability, typically those beyond 2.3.1. Organizations must implement comprehensive input validation and output escaping mechanisms for all user-facing data processing within the application. Web Application Firewall rules can provide additional protection by filtering known malicious patterns in incoming requests. Regular security audits should verify proper sanitization of all dynamic content and implement Content Security Policy headers to limit script execution. System administrators should monitor affected sites for signs of exploitation and ensure that all WordPress core files, themes, and plugins remain updated according to best practices established by wordpress.org security recommendations. The vulnerability highlights the critical importance of maintaining up-to-date software components and implementing defense-in-depth strategies for web application security.