CVE-2025-62255 is a cross-site scripting (XSS) vulnerability classified under CWE-79, found in Liferay Portal versions 7.4.0 through 7.4.3.101 and Liferay DXP 2023.Q3.1 through 2023.Q3.5, including 7.4 GA through update 92. The vulnerability occurs on the edit Knowledge Base article page, where an attacker can inject arbitrary web scripts or HTML by crafting a malicious payload embedded in an attachment's filename. This input is not properly neutralized during web page generation, allowing the injected script to execute in the context of the victim's browser session. The vulnerability is characterized as a self XSS, meaning the attack requires the victim to interact with the malicious payload, typically by opening or editing the affected Knowledge Base article. The CVSS 4.0 score is 2.0, indicating low severity due to high attack complexity, requirement for user interaction, and limited impact on confidentiality and integrity. The vulnerability does not require elevated privileges but does require low privileges and user interaction. No public exploits or active exploitation have been reported to date. The issue stems from insufficient input validation and output encoding of attachment filenames, which are reflected unsafely in the web interface. This flaw could be leveraged to execute scripts that steal session tokens, manipulate page content, or perform actions on behalf of the user within the Liferay Portal environment. The vulnerability affects both supported and older unsupported versions, emphasizing the need for patching or compensating controls. No official patches or updates are linked, suggesting organizations should monitor vendor advisories closely.

For European organizations, the impact of CVE-2025-62255 is primarily on confidentiality and integrity within the Liferay Portal environment. Successful exploitation could allow attackers to execute arbitrary scripts in the context of authenticated users, potentially leading to session hijacking, unauthorized actions, or data manipulation within the Knowledge Base. However, the requirement for user interaction and low privileges limits the attacker's ability to escalate or propagate the attack widely. Availability is not affected. Organizations relying on Liferay Portal for internal knowledge management or customer-facing portals could face reputational damage and operational disruption if sensitive information is compromised or altered. The risk is heightened in sectors where Liferay is used for critical documentation or collaboration, such as government, finance, and healthcare. Since no known exploits are active, the immediate threat is low, but the vulnerability could be exploited in targeted phishing or social engineering campaigns. European entities with large deployments or those integrating Liferay with other critical systems should assess their exposure carefully.

1. Apply official patches or updates from Liferay as soon as they become available to address CVE-2025-62255. 2. Implement strict input validation and output encoding on attachment filenames to neutralize potentially malicious scripts before rendering. 3. Enforce Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts within the portal. 4. Limit user privileges on the Knowledge Base article edit page to trusted personnel only, reducing the risk of malicious payload injection. 5. Educate users about the risks of interacting with untrusted or unexpected attachments and filenames within the portal. 6. Monitor logs and user activity for unusual behavior indicative of attempted XSS exploitation. 7. Consider disabling attachment filename rendering or sanitizing filenames on upload if patching is delayed. 8. Conduct regular security assessments and penetration testing focused on web application vulnerabilities in the Liferay environment. 9. Use web application firewalls (WAFs) with rules targeting XSS attack patterns to provide an additional layer of defense.