CVE-2025-62254 is a vulnerability classified under CWE-22 (Improper Limitation of a Pathname to a Restricted Directory) found in the ComboServlet component of Liferay Portal and Liferay DXP across multiple versions including 7.4.0 through 7.4.3.111 and various older supported and unsupported releases. The ComboServlet is designed to combine multiple files into a single HTTP response to optimize web resource loading. However, it does not impose limits on the number or cumulative size of files that can be combined via the URL query string. This lack of limitation enables a remote attacker to craft a specially formed URL that requests an excessive number or size of files, causing the server to generate an extremely large response. The resulting resource consumption can overwhelm server memory and processing capacity, leading to a denial of service (DoS) condition. The vulnerability can be exploited remotely without requiring authentication or user interaction, increasing its risk profile. Although the CWE-22 classification suggests a path traversal issue, the primary impact here is DoS due to resource exhaustion rather than unauthorized file access or data disclosure. No public exploits have been reported yet, and no official patches are currently linked, indicating that organizations should proactively monitor and mitigate this risk. The CVSS v4.0 score of 6.9 (medium severity) reflects the network attack vector, no required privileges or user interaction, and limited impact on confidentiality and integrity but significant availability impact.

For European organizations, the primary impact of CVE-2025-62254 is the potential for denial of service attacks against Liferay Portal instances. Organizations relying on Liferay for public-facing websites, intranets, or digital services may experience service outages or degraded performance if exploited. This can disrupt business operations, customer access, and internal workflows. Critical sectors such as government, finance, healthcare, and telecommunications that use Liferay Portal for content management and service delivery are particularly at risk. The vulnerability’s ease of remote exploitation without authentication increases the likelihood of opportunistic attacks. Additionally, denial of service incidents can lead to reputational damage and potential regulatory scrutiny under European data protection and service availability requirements. While no data breach or integrity compromise is indicated, the availability impact alone can have significant operational and financial consequences.

To mitigate CVE-2025-62254, European organizations should implement the following specific measures: 1) Monitor and restrict the length and complexity of URL query strings targeting the ComboServlet to prevent excessively large requests. 2) Deploy web application firewalls (WAFs) with custom rules to detect and block requests attempting to combine an unusually high number or size of files. 3) Apply any official patches or updates from Liferay promptly once released. 4) Implement rate limiting and request throttling on endpoints serving the ComboServlet to reduce the risk of resource exhaustion. 5) Conduct regular security assessments and penetration tests focusing on URL parameter manipulation. 6) Review and harden server resource allocation and timeout settings to minimize impact from large response generation. 7) Consider isolating or segmenting Liferay Portal instances to limit blast radius in case of DoS. 8) Maintain up-to-date incident response plans to quickly identify and mitigate DoS attacks. These targeted actions go beyond generic advice by focusing on the specific attack vector and component involved.