CVE-2024-23889 is a high-severity Cross-Site Scripting (XSS) vulnerability identified in version 1.0 of Cups Easy (Purchase & Inventory), a software product used for purchase and inventory management. The vulnerability arises due to improper neutralization of user-supplied input in the web application, specifically in the 'itemgroupid' parameter of the /cupseasylive/itemgroupcreate.php endpoint. Because the input is not sufficiently encoded or sanitized before being reflected in the web page, an attacker can craft a malicious URL containing executable script code. When an authenticated user clicks this URL, the malicious script executes in their browser context. This can lead to theft of session cookies, enabling the attacker to hijack the user's session and potentially perform unauthorized actions within the application. The CVSS v3.1 base score is 8.2, reflecting the network attack vector (no physical or local access needed), low attack complexity, no privileges required, but user interaction is necessary (the victim must click the malicious link). The scope is changed, indicating that the vulnerability affects components beyond the initially vulnerable module. The impact on confidentiality is high due to session cookie theft, integrity impact is low, and availability is unaffected. No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability was published on January 26, 2024, and assigned by INCIBE. This vulnerability falls under CWE-79, which is a common and well-understood web application security flaw.

For European organizations using Cups Easy (Purchase & Inventory) version 1.0, this vulnerability poses a significant risk to the confidentiality of user sessions and potentially sensitive business data managed within the application. Successful exploitation could allow attackers to impersonate legitimate users, leading to unauthorized access to purchase and inventory records, manipulation of data, or fraudulent transactions. This could disrupt supply chain operations, financial reporting, and inventory management processes. Given that the vulnerability requires user interaction and an authenticated session, phishing or social engineering campaigns could be used to trick employees into clicking malicious links. The impact is particularly critical for organizations with high-value inventory or sensitive procurement data. Additionally, session hijacking could facilitate lateral movement within the corporate network if the application integrates with other internal systems. The lack of a patch at the time of disclosure increases the urgency for mitigation. Compliance with European data protection regulations (e.g., GDPR) could be jeopardized if personal or sensitive data is exposed due to this vulnerability, potentially leading to legal and reputational consequences.

1. Immediate mitigation should focus on user awareness and training to recognize and avoid clicking suspicious or unsolicited URLs related to the Cups Easy application. 2. Implement strict Content Security Policy (CSP) headers on the web server hosting Cups Easy to restrict the execution of unauthorized scripts and reduce the impact of XSS attacks. 3. Use web application firewalls (WAFs) with rules designed to detect and block XSS attack patterns targeting the 'itemgroupid' parameter or the vulnerable endpoint. 4. Enforce multi-factor authentication (MFA) for accessing the Cups Easy application to reduce the risk of session hijacking leading to unauthorized access. 5. Monitor application logs and network traffic for unusual activity that could indicate exploitation attempts, such as repeated access to the vulnerable URL with suspicious parameters. 6. If possible, apply input validation and output encoding controls at the application level as a temporary fix, such as sanitizing the 'itemgroupid' parameter before rendering. 7. Coordinate with the vendor for an official patch or update and plan for prompt deployment once available. 8. Review session management policies to ensure cookies are marked HttpOnly and Secure to limit exposure to theft via XSS.