CVE-2025-54024 is a medium-severity vulnerability classified under CWE-79, which pertains to improper neutralization of input during web page generation, commonly known as Cross-site Scripting (XSS). Specifically, this vulnerability affects the WPAdverts plugin developed by Greg Winiarski, up to version 2.2.5. The vulnerability is DOM-based XSS, meaning that the malicious script is executed as a result of modifying the DOM environment in the victim’s browser, rather than being directly injected into the HTML response from the server. This type of XSS occurs when client-side scripts write data provided by the user to the Document Object Model without proper sanitization or escaping. The CVSS 3.1 score of 6.5 indicates a medium severity with the vector AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L, meaning the attack can be launched remotely over the network with low attack complexity, requires low privileges and user interaction, and impacts confidentiality, integrity, and availability to a limited extent but with scope changed (affecting resources beyond the vulnerable component). The vulnerability allows an attacker with some level of authenticated access (PR:L) to craft malicious input that, when viewed by other users or the attacker themselves, can execute arbitrary JavaScript in the context of the victim’s browser session. This can lead to session hijacking, defacement, or redirection to malicious sites. No public exploits are currently known in the wild, and no patches have been linked yet, indicating that the vulnerability is newly disclosed and may not yet be widely exploited. However, the presence of this vulnerability in a popular WordPress advertising plugin poses a risk to websites using WPAdverts for classified ads or similar functionality, as attackers could leverage it to compromise site visitors or administrators.

For European organizations, the impact of this DOM-based XSS vulnerability in WPAdverts can be significant, especially for businesses relying on WordPress sites for advertising, classifieds, or marketplace services. Exploitation could lead to unauthorized access to user sessions, theft of sensitive information such as cookies or credentials, and potential defacement or manipulation of website content. This undermines user trust and can result in reputational damage, regulatory scrutiny under GDPR for failure to protect user data, and potential financial losses. Since the vulnerability requires low privileges but user interaction, phishing or social engineering could be used to trigger the exploit. The scope change (S:C) indicates that the attack can affect resources beyond the vulnerable plugin, potentially impacting other parts of the website or connected systems. Given the widespread use of WordPress and plugins like WPAdverts across Europe, the risk extends to a broad range of sectors including e-commerce, classifieds, real estate, and local business directories. Organizations with high web traffic or sensitive user data are particularly at risk.

To mitigate this vulnerability, European organizations should immediately audit their WordPress installations to identify the use of WPAdverts plugin versions up to 2.2.5. Until an official patch is released, consider the following specific actions: 1) Apply Web Application Firewall (WAF) rules that detect and block typical DOM-based XSS payloads targeting WPAdverts. 2) Restrict user input fields related to WPAdverts to accept only expected characters and implement client-side and server-side input validation and sanitization. 3) Limit the privileges of users who can input data into WPAdverts to reduce the risk of malicious input. 4) Educate users and administrators about the risk of clicking suspicious links or interacting with untrusted content on affected sites. 5) Monitor logs for unusual activity or error messages related to WPAdverts. 6) Once a patch is available, prioritize immediate updating of the plugin to the fixed version. 7) Consider isolating the WPAdverts plugin functionality or using Content Security Policy (CSP) headers to restrict script execution contexts, thereby reducing the impact of potential XSS payloads.