CVE-2023-29052 is a cross-site scripting (XSS) vulnerability identified in the OX App Suite developed by Open-Xchange GmbH. The issue stems from improper neutralization of input during web page generation, specifically in the handling of user-defined disclaimer texts within an upsell shop dialog. These disclaimer texts were not correctly sanitized, allowing attackers to embed malicious JavaScript code. When a victim accesses a user account containing such malicious script code, the script executes in the context of the trusted domain, potentially leading to unauthorized actions such as session hijacking, data theft, or manipulation of the user interface. The vulnerability requires the attacker to have at least limited authenticated access (PR:L) and the victim to interact with the malicious content (UI:R). The CVSS v3.1 score is 5.4, indicating a medium severity level, with an attack vector over the network (AV:N), low attack complexity (AC:L), and scope change (S:C) due to the potential impact on other components or users. No public exploits have been reported, but the vulnerability poses a risk to confidentiality and integrity without affecting availability. The vendor has addressed the issue by adding proper sanitization for the affected content. Organizations using OX App Suite should verify their versions and apply the necessary updates to mitigate this risk.

For European organizations, the impact of CVE-2023-29052 can be significant, especially for those relying on OX App Suite for email, collaboration, and productivity services. Successful exploitation could lead to unauthorized script execution within user sessions, enabling attackers to steal sensitive information such as credentials, personal data, or corporate communications. This can result in data breaches, loss of user trust, and potential regulatory penalties under GDPR. The integrity of user data and application behavior may be compromised, potentially facilitating further attacks like phishing or lateral movement within networks. Although availability is not directly affected, the reputational damage and operational disruptions caused by data compromise can be substantial. The requirement for authenticated access and user interaction somewhat limits the attack surface but does not eliminate risk, particularly in environments with many users and frequent external communications. Organizations in sectors with high confidentiality demands, such as finance, healthcare, and government, are particularly vulnerable to the consequences of such XSS attacks.

To mitigate CVE-2023-29052, European organizations should: 1) Immediately apply the vendor-provided patches or updates that implement proper sanitization of user-defined disclaimer texts in OX App Suite. 2) Restrict the ability of users to input HTML or script content in fields that are rendered in web dialogs, employing strict input validation and output encoding. 3) Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts and reduce the impact of potential XSS attacks. 4) Conduct regular security audits and penetration testing focusing on web application input handling and user-generated content. 5) Educate users about the risks of interacting with suspicious links or dialogs, especially within internal applications. 6) Monitor logs and user activity for unusual behavior indicative of XSS exploitation attempts. 7) Consider deploying web application firewalls (WAFs) with rules tuned to detect and block XSS payloads targeting OX App Suite. 8) Maintain a robust patch management process to ensure timely updates of all software components.