CVE-2025-43796 is a high-severity vulnerability affecting multiple versions of Liferay Portal and Liferay DXP, specifically versions 7.3 GA through update 35, 7.4.0 through 7.4.3.101, and 2023.Q3.0 through 2023.Q3.4. The vulnerability arises from the lack of limits on the number of objects returned by GraphQL queries within these products. GraphQL is a query language for APIs that allows clients to request exactly the data they need. However, in this case, the Liferay Portal does not impose any restrictions on the size or complexity of the queries, enabling remote attackers to craft queries that request an excessive number of objects. This uncontrolled resource consumption leads to a denial-of-service (DoS) condition by exhausting server resources such as CPU, memory, or database connections, thereby degrading or completely disrupting the availability of the affected application. The vulnerability is classified under CWE-400 (Uncontrolled Resource Consumption), indicating that the system fails to properly limit resource usage. The CVSS 4.0 base score of 7.1 reflects a high severity, with attack vector being network-based (AV:N), low attack complexity (AC:L), no privileges required (PR:L indicates low privileges but not none, which suggests some minimal privileges are needed), no user interaction (UI:N), and a high impact on availability (VA:H). There is no known exploit in the wild at the time of publication, and no official patches have been linked yet. The vulnerability affects critical enterprise portal software widely used for building websites, intranets, and digital experiences, making it a significant risk for organizations relying on these versions of Liferay Portal or DXP.

For European organizations, the impact of CVE-2025-43796 can be substantial. Liferay Portal is commonly used by enterprises, government agencies, and public sector organizations across Europe to manage digital content and provide web services. A successful exploitation could lead to denial-of-service conditions, rendering critical web portals and digital services unavailable. This disruption can affect internal business operations, customer-facing services, and public information dissemination. The unavailability of portals may also impact compliance with regulatory requirements for service continuity and data accessibility, particularly in sectors like finance, healthcare, and government. Additionally, the resource exhaustion could indirectly facilitate further attacks by distracting or overwhelming security monitoring systems. Given the vulnerability requires only low privileges and no user interaction, attackers with minimal access could trigger DoS attacks remotely, increasing the risk surface. The absence of known exploits currently provides a window for mitigation, but the high severity score and ease of exploitation underscore the urgency for European organizations to address this issue promptly.

To mitigate CVE-2025-43796 effectively, European organizations should implement several specific measures beyond generic advice: 1) Apply any available patches or updates from Liferay as soon as they are released. Since no patch links are currently available, organizations should monitor Liferay’s official channels closely. 2) Implement rate limiting and query complexity analysis on GraphQL endpoints to restrict the number of objects returned per query and prevent excessively large or complex queries from being processed. This can be done by configuring API gateways or web application firewalls (WAFs) that support GraphQL-specific protections. 3) Enforce strict authentication and authorization controls to limit access to GraphQL APIs, ensuring that only trusted and necessary users or systems can execute queries. 4) Monitor server resource usage and implement anomaly detection to identify unusual spikes in GraphQL query volume or resource consumption indicative of an attack. 5) Consider deploying network-level protections such as IP reputation filtering and geo-blocking to reduce exposure to untrusted sources. 6) Conduct internal security assessments and penetration testing focused on GraphQL endpoints to identify and remediate similar resource exhaustion risks. 7) Educate development and operations teams about secure GraphQL practices, including query depth limiting and complexity scoring, to prevent future vulnerabilities.