CVE-2022-28980 is a medium-severity cross-site scripting (XSS) vulnerability affecting Liferay Portal version 7.4.3.4 and Liferay DXP version 7.4 GA. The vulnerability arises from improper sanitization of input parameters prefixed with 'filter_' which allows attackers to inject and execute arbitrary web scripts or HTML code within the context of the vulnerable web application. This type of vulnerability is classified under CWE-79, indicating that it is a classic reflected or stored XSS issue. Exploitation requires no privileges (PR:N) but does require user interaction (UI:R), such as tricking a user into clicking a crafted link or submitting malicious input. The vulnerability has a CVSS v3.1 base score of 6.1, reflecting a medium severity level. The attack vector is network-based (AV:N), with low attack complexity (AC:L), and the impact affects confidentiality and integrity partially (C:L/I:L) but does not impact availability (A:N). The scope is changed (S:C), meaning the vulnerability affects resources beyond the security scope of the vulnerable component, potentially allowing an attacker to access or manipulate data in a different security context. No known exploits are currently reported in the wild, and no official patches or vendor advisories are linked in the provided data. The vulnerability could be leveraged to steal sensitive session cookies, perform actions on behalf of authenticated users, or deface web content, depending on the privileges of the victim user and the application context. Given that Liferay Portal and DXP are widely used enterprise portal platforms for content management, collaboration, and intranet/extranet services, this vulnerability could be significant in environments where these products are deployed without adequate input validation or output encoding controls.

For European organizations, the impact of CVE-2022-28980 can be considerable, especially for those relying on Liferay Portal or Liferay DXP for critical business functions such as internal communications, document management, and customer-facing portals. Successful exploitation could lead to unauthorized disclosure of sensitive information (e.g., session tokens, personal data), manipulation of displayed content, or phishing attacks targeting employees or customers. This could result in reputational damage, regulatory non-compliance (notably under GDPR), and potential financial losses. Since the vulnerability affects confidentiality and integrity but not availability, the primary risks involve data leakage and unauthorized actions rather than service disruption. The requirement for user interaction means social engineering or phishing campaigns might be necessary to exploit the vulnerability effectively. However, given the widespread use of web browsers and the internet, the attack surface remains significant. Organizations with public-facing Liferay portals are at higher risk, as attackers can lure external users, whereas internal portals might be somewhat protected by network segmentation but still vulnerable to insider threats or phishing. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially if attackers develop proof-of-concept code or weaponize the vulnerability in the future.

To mitigate CVE-2022-28980, European organizations should prioritize the following actions: 1) Apply official patches or updates from Liferay as soon as they become available, since no patch links were provided, organizations should monitor Liferay's security advisories closely. 2) Implement robust input validation and output encoding on all user-supplied data, especially parameters with the 'filter_' prefix, to neutralize malicious scripts before rendering. 3) Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of XSS attacks. 4) Conduct regular security assessments and penetration testing focusing on web application vulnerabilities, including XSS. 5) Educate users and administrators about phishing and social engineering tactics to reduce the likelihood of successful exploitation requiring user interaction. 6) Utilize web application firewalls (WAFs) configured to detect and block common XSS attack patterns targeting Liferay portals. 7) Review and harden session management controls to limit the damage from stolen session cookies, including setting HttpOnly and Secure flags on cookies. 8) Isolate critical Liferay instances behind VPNs or internal networks where feasible to reduce exposure to external attackers. These targeted measures go beyond generic advice by focusing on the specific characteristics of the vulnerability and the affected platform.