CVE-2025-46534 is a DOM-based Cross-site Scripting (XSS) vulnerability classified under CWE-79, affecting the DanielRiera Image Style Hover plugin up to version 1.0.6. The vulnerability arises from improper neutralization of user-supplied input during web page generation, allowing malicious scripts to be injected and executed in the context of the victim's browser. Specifically, the flaw exists in the way the plugin processes input that is reflected in the Document Object Model (DOM) without adequate sanitization or encoding, enabling attackers to craft URLs or payloads that trigger script execution when a user interacts with the affected web page. This type of XSS is client-side and does not necessarily require server-side code injection, making it harder to detect and mitigate through traditional server-side filtering. The vulnerability does not currently have any known exploits in the wild, and no official patches have been released as of the publication date (April 24, 2025). The plugin is commonly used to add hover effects to images on websites, which means the vulnerability could be triggered when users hover over or interact with images styled by this plugin. Given the nature of DOM-based XSS, the attack vector often involves social engineering or tricking users into visiting crafted URLs or interacting with malicious content embedded in otherwise legitimate pages.

For European organizations, the impact of this vulnerability can be significant, particularly for those relying on the DanielRiera Image Style Hover plugin in their web presence. Successful exploitation can lead to session hijacking, theft of sensitive user data such as cookies or authentication tokens, defacement of web content, or redirection to malicious sites. This undermines the confidentiality and integrity of user interactions and can damage organizational reputation. Sectors with high web traffic or sensitive user data, such as e-commerce, finance, healthcare, and government services, are especially at risk. Additionally, the vulnerability could be leveraged as a stepping stone for more complex attacks, including phishing campaigns or malware distribution. While the vulnerability requires user interaction (e.g., visiting a maliciously crafted URL or interacting with a compromised page element), the ease of exploitation is moderate due to the widespread use of web browsers and the commonality of image hover effects on websites. The absence of known exploits in the wild suggests that immediate risk is moderate, but the potential for future exploitation remains, especially if attackers develop automated tools targeting this flaw.

Organizations should take proactive steps to mitigate this vulnerability beyond generic advice. First, they should audit their web assets to identify any usage of the DanielRiera Image Style Hover plugin, particularly versions up to 1.0.6. If the plugin is in use, temporarily disabling it or removing hover effects until a patch is available is advisable. Web developers should implement strict input validation and output encoding on all user-controllable inputs reflected in the DOM, employing context-aware encoding techniques (e.g., JavaScript string encoding, HTML entity encoding) to neutralize malicious scripts. Content Security Policy (CSP) headers should be configured to restrict the execution of inline scripts and limit sources of executable code, reducing the impact of potential XSS payloads. Additionally, organizations should monitor web traffic and logs for unusual URL patterns or user reports of suspicious behavior related to image hover interactions. User awareness campaigns can help reduce the risk of social engineering attacks exploiting this vulnerability. Finally, staying informed about vendor updates and applying patches promptly once available is critical to long-term mitigation.