CVE-2022-28979 is a cross-site scripting (XSS) vulnerability identified in multiple versions of Liferay Portal (v7.1.0 through v7.4.2) and Liferay DXP (7.1 before fix pack 26, 7.2 before fix pack 15, and 7.3 before service pack 3). The vulnerability resides in the Portal Search module's Custom Facet widget, specifically in the Custom Parameter Name text field. An attacker can inject crafted payloads containing arbitrary web scripts or HTML into this field, which are then executed in the context of users viewing the affected portal pages. This type of vulnerability is classified under CWE-79, indicating improper neutralization of input during web page generation. The CVSS v3.1 base score is 6.1, reflecting a medium severity level. The attack vector is network-based (AV:N), requires no privileges (PR:N), but does require user interaction (UI:R) such as clicking a malicious link or visiting a compromised page. The scope is changed (S:C), meaning the vulnerability can affect resources beyond the vulnerable component. The impact affects confidentiality and integrity to a limited extent (C:L, I:L) but does not impact availability (A:N). No known exploits are currently reported in the wild, and no official patches or fix links were provided in the source information. The vulnerability could allow attackers to steal session tokens, perform actions on behalf of users, or deface web content, depending on the portal's configuration and user privileges.

For European organizations using Liferay Portal or Liferay DXP within the affected versions, this vulnerability poses a risk primarily to web application security and user data confidentiality. Exploitation could lead to session hijacking, unauthorized actions, or phishing attacks leveraging the trusted portal interface. Organizations relying on Liferay for intranet portals, customer-facing websites, or digital experience platforms may face reputational damage, data leakage, and potential regulatory compliance issues under GDPR if personal data is compromised. The medium severity indicates that while the vulnerability is not critical, it can be leveraged in targeted attacks, especially if combined with social engineering. The requirement for user interaction means that phishing or social engineering campaigns could be used to trigger the exploit. Given the widespread use of Liferay in enterprise environments across Europe, especially in sectors like government, education, and large enterprises, the impact could be significant if not addressed promptly.

1. Immediate application of official patches or fix packs from Liferay once available is the primary mitigation step. Organizations should monitor Liferay's security advisories for updates. 2. In the absence of patches, implement input validation and output encoding on the Custom Parameter Name field to neutralize malicious scripts. 3. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts within the portal environment. 4. Conduct regular security audits and penetration testing focusing on the Portal Search module and Custom Facet widget to detect injection points. 5. Educate users about phishing risks and suspicious links to reduce the likelihood of successful user interaction exploitation. 6. Consider deploying Web Application Firewalls (WAFs) with custom rules to detect and block malicious payloads targeting this vulnerability. 7. Review and restrict user privileges to minimize the impact of any successful XSS exploitation, ensuring least privilege principles are enforced.