CVE-2025-43746 is a reflected Cross-Site Scripting (XSS) vulnerability affecting multiple versions of the Liferay Portal and Liferay DXP products, specifically versions 7.4.0 through 7.4.3.132 and various quarterly releases from 2024.Q1 through 2025.Q2. This vulnerability arises from improper sanitization of user-supplied input in the parameters _com_liferay_dynamic_data_mapping_web_portlet_DDMPortlet_portletNamespace and _com_liferay_dynamic_data_mapping_web_portlet_DDMPortlet_namespace. An authenticated remote attacker can exploit this flaw by injecting malicious JavaScript code into these parameters, which is then reflected back to the victim's browser without adequate encoding or filtering. The vulnerability is classified under CWE-79, indicating a failure to properly neutralize input leading to script injection. The CVSS v4.0 base score is 5.1 (medium severity), reflecting that the attack vector is network-based, requires low attack complexity, no user interaction, but does require high privileges (authenticated user). The impact on confidentiality, integrity, and availability is low, but the vulnerability can be leveraged to execute arbitrary scripts in the context of the victim's browser session, potentially leading to session hijacking, unauthorized actions, or information disclosure within the portal environment. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability affects a widely used enterprise portal platform that integrates content management, collaboration, and web publishing capabilities, making it a relevant concern for organizations relying on Liferay for internal or external web services.

For European organizations, the impact of this vulnerability can be significant depending on their use of Liferay Portal or DXP products. Since Liferay is commonly deployed in enterprise environments for intranet portals, customer-facing websites, and digital experience platforms, exploitation could allow attackers to execute malicious scripts within authenticated sessions. This could lead to unauthorized actions such as privilege escalation, data theft, or manipulation of portal content. The requirement for authenticated access limits the attack surface to internal or registered users, but insider threats or compromised credentials could facilitate exploitation. Additionally, the reflected XSS could be used in targeted phishing campaigns against employees or partners to steal session tokens or credentials. The medium severity rating suggests that while the vulnerability is not critical, it still poses a tangible risk to confidentiality and integrity of portal data and user sessions. Organizations in sectors with strict data protection regulations, such as finance, healthcare, and government, may face compliance risks if this vulnerability is exploited to leak sensitive information. The absence of known exploits in the wild currently reduces immediate risk but does not preclude future exploitation attempts.

1. Apply patches or updates from Liferay as soon as they become available to address this vulnerability. Monitor official Liferay security advisories regularly. 2. Implement strict input validation and output encoding on the affected parameters (_com_liferay_dynamic_data_mapping_web_portlet_DDMPortlet_portletNamespace and _namespace) to neutralize malicious scripts. This can be done by customizing the portal's input handling or using web application firewalls (WAF) with rules targeting these parameters. 3. Enforce the principle of least privilege for user accounts to minimize the risk posed by compromised credentials, since the vulnerability requires authenticated access. 4. Conduct security awareness training to help users recognize phishing attempts that might leverage this vulnerability. 5. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in the browser context, mitigating the impact of XSS attacks. 6. Regularly audit and monitor portal logs for unusual activities that might indicate exploitation attempts. 7. Consider isolating or segmenting the Liferay portal environment to limit lateral movement if an attack occurs.