CVE-2025-60124 is a security vulnerability classified as CWE-79, which pertains to Improper Neutralization of Input During Web Page Generation, commonly known as Cross-site Scripting (XSS). This vulnerability affects the Simple Colorbox product developed by Ryan Hellyer, specifically versions up to and including 1.6.1. The nature of the vulnerability is a Stored XSS, meaning that malicious input submitted by an attacker is persistently stored by the application and later rendered in web pages without proper sanitization or encoding. This allows an attacker to inject malicious scripts that execute in the context of other users' browsers when they view the affected pages. The CVSS v3.1 base score is 6.5, indicating a medium severity level. The vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L) reveals that the attack can be performed remotely over the network (AV:N) with low attack complexity (AC:L), requires privileges (PR:L) and user interaction (UI:R), and impacts confidentiality, integrity, and availability to a limited extent (C:L, I:L, A:L). The scope is changed (S:C), meaning the vulnerability affects components beyond the initially vulnerable component. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability arises because the application fails to properly neutralize or encode user-supplied input before including it in dynamically generated web pages, allowing malicious JavaScript code to be stored and executed in other users' browsers. This can lead to session hijacking, defacement, or redirection to malicious sites.

For European organizations using Simple Colorbox, this vulnerability poses a significant risk to web application security, particularly for those that rely on this component for user interface elements involving color selection or display. Exploitation of this Stored XSS vulnerability could lead to unauthorized disclosure of sensitive information, such as session cookies or authentication tokens, enabling attackers to impersonate legitimate users. This can result in data breaches, unauthorized transactions, or manipulation of user accounts. Additionally, the integrity of the web application can be compromised by injecting malicious content or scripts, potentially damaging the organization's reputation and trustworthiness. Availability impact, while limited, could occur if injected scripts perform actions that disrupt normal user interactions or cause browser crashes. Given the medium severity and requirement for some level of privilege and user interaction, the threat is moderate but should not be underestimated, especially in sectors with high regulatory requirements such as finance, healthcare, and government within Europe. Failure to address this vulnerability could also lead to non-compliance with GDPR and other data protection regulations if personal data is exposed or mishandled.

To mitigate CVE-2025-60124 effectively, European organizations should first verify if they are using Simple Colorbox versions up to 1.6.1 and plan for immediate upgrade once a patched version is released by the vendor. In the absence of an official patch, organizations should implement strict input validation and output encoding on all user-supplied data that is rendered in web pages. Employing Content Security Policy (CSP) headers can help reduce the impact of XSS by restricting the execution of unauthorized scripts. Additionally, web application firewalls (WAFs) can be configured to detect and block common XSS attack patterns targeting this vulnerability. Regular security code reviews and penetration testing focusing on XSS vectors should be conducted to identify and remediate similar issues proactively. User privileges should be minimized to reduce the risk of exploitation, and user awareness training should emphasize the dangers of interacting with untrusted content. Monitoring logs for unusual activity related to web input fields associated with Simple Colorbox can provide early detection of exploitation attempts.