CVE-2025-62254 is a path traversal vulnerability categorized under CWE-22 affecting the ComboServlet component of Liferay Portal and Liferay DXP across multiple versions, including 7.4.0 through 7.4.3.111 and various 2023 Q3 and Q4 releases. The vulnerability arises because the ComboServlet does not impose limits on the number or size of files it combines based on the URL query string parameters. Attackers can exploit this by sending specially crafted HTTP requests that cause the servlet to generate excessively large combined responses. This can overwhelm server resources, leading to denial of service (DoS) conditions that degrade or disrupt service availability. The vulnerability requires no authentication or user interaction and can be triggered remotely over the network, increasing its risk profile. Although no public exploits have been reported yet, the flaw’s presence in widely deployed Liferay Portal versions used by enterprises and governments worldwide makes it a significant concern. The CVSS 4.0 base score of 6.9 reflects a medium severity, primarily due to the impact on availability and the ease of exploitation. The vulnerability does not affect confidentiality or integrity directly but can cause service outages. Mitigation currently relies on vendor patches when released, but in their absence, network-level controls and application-layer request filtering can reduce exposure. Organizations should audit their Liferay Portal deployments to identify affected versions and implement compensating controls promptly.

The primary impact of CVE-2025-62254 is on the availability of Liferay Portal services. Exploitation can lead to denial of service by forcing the server to generate very large HTTP responses, consuming excessive CPU, memory, and bandwidth resources. For European organizations, this can disrupt critical web portals, intranet services, and customer-facing applications that rely on Liferay Portal, potentially causing operational downtime and loss of business continuity. Public sector entities, financial institutions, and large enterprises using Liferay for digital services may face reputational damage and regulatory scrutiny if service disruptions occur. Additionally, the lack of authentication requirement means attackers can exploit the vulnerability remotely without prior access, increasing the attack surface. While confidentiality and integrity are not directly impacted, the availability disruption can indirectly affect business processes and user trust. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the potential for future attacks. European organizations with high traffic volumes or limited capacity to absorb large response payloads are particularly vulnerable to DoS impacts.

1. Monitor Liferay’s official security advisories and apply vendor patches promptly once available to address CVE-2025-62254. 2. Until patches are released, restrict access to the ComboServlet endpoint using network segmentation, IP whitelisting, or web server access controls to limit exposure. 3. Implement web application firewall (WAF) rules to detect and block requests with suspiciously large or numerous file parameters in the URL query string targeting the ComboServlet. 4. Configure rate limiting and request size limits at the web server or reverse proxy level to prevent resource exhaustion from large or frequent requests. 5. Conduct regular security audits of Liferay Portal configurations and logs to detect anomalous request patterns indicative of exploitation attempts. 6. Consider deploying DoS mitigation solutions that can absorb or filter large HTTP responses to maintain service availability. 7. Educate IT and security teams about this vulnerability to ensure rapid response and incident handling if exploitation is suspected. 8. Evaluate the necessity of public exposure of the ComboServlet and disable or restrict it if not required for business operations.