CVE-2025-43826 is a stored cross-site scripting (XSS) vulnerability identified in multiple versions of Liferay Portal, including versions 7.4.0 through 7.4.3.112, older unsupported versions, and various releases of Liferay DXP from 2023.Q3.1 through 2023.Q4.8. The vulnerability arises from improper neutralization of input during web page generation, specifically within the Web Content translation feature. Attackers can exploit this flaw by injecting arbitrary web scripts or HTML code into any rich text field of a web content article. When other users view the affected content, the malicious script executes in their browsers, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of the victim. The vulnerability is classified under CWE-79, indicating improper input sanitization that allows script injection. The CVSS v4.0 base score is 4.8, reflecting a medium severity level. The vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L - low privileges), user interaction required (UI:A), and low impact on confidentiality, integrity, and availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. This vulnerability affects a widely used enterprise portal platform, often deployed in corporate intranets and public-facing websites, making it a significant concern for organizations relying on Liferay for content management and collaboration.

For European organizations, the impact of this XSS vulnerability can be substantial, especially for those using Liferay Portal as a core component of their digital infrastructure. Exploitation could lead to unauthorized access to user sessions, enabling attackers to impersonate legitimate users and potentially access sensitive corporate data or internal systems. This can result in data breaches, loss of customer trust, and compliance violations under regulations such as GDPR. Additionally, attackers might leverage the vulnerability to distribute malware or conduct phishing campaigns by injecting malicious scripts into trusted web pages. Given the collaborative nature of portals, the spread of malicious content could affect multiple departments or subsidiaries within an organization. The medium severity score suggests that while the vulnerability is not trivially exploitable without some user interaction, the potential for damage remains significant, particularly in environments with privileged users or sensitive data accessible via the portal.

Organizations should prioritize the following specific mitigation steps: 1) Immediately audit all Liferay Portal instances to identify affected versions and plan for upgrades to patched versions once available. 2) Implement strict input validation and output encoding on all rich text fields, especially those used in web content translations, to neutralize potentially malicious scripts. 3) Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts within the portal environment. 4) Limit user privileges to the minimum necessary, reducing the risk that low-privilege users can inject malicious content. 5) Monitor web content submissions for unusual or suspicious script patterns using automated scanning tools. 6) Educate users about the risks of interacting with unexpected or suspicious content within the portal. 7) If immediate patching is not possible, consider temporarily disabling or restricting access to the Web Content translation feature to reduce exposure. 8) Regularly review and update security configurations and conduct penetration testing focused on XSS vectors within the portal.