CVE-2025-48988 is a resource allocation vulnerability classified under CWE-770, affecting Apache Tomcat versions from 8.5.0 through 11.0.7, including some end-of-life versions. The flaw arises because Tomcat does not impose sufficient limits or throttling on resource allocation, allowing an attacker to consume excessive server resources such as memory, CPU, or threads. This can be triggered remotely without authentication or user interaction, making it a network-exploitable denial of service vector. The vulnerability impacts the availability of Tomcat servers by potentially causing crashes or severe performance degradation. Apache has addressed this issue in versions 11.0.8, 10.1.42, and 9.0.106 by introducing proper resource management and throttling mechanisms. Although no exploits have been observed in the wild yet, the vulnerability’s characteristics and CVSS score of 7.5 indicate a significant risk, especially for internet-facing Tomcat deployments. Organizations relying on Tomcat for critical web applications should prioritize upgrading and monitoring resource consumption to prevent exploitation.

For European organizations, the primary impact is denial of service leading to downtime of web applications and services hosted on vulnerable Apache Tomcat servers. This can disrupt business operations, degrade customer experience, and potentially cause financial losses. Public sector entities, financial institutions, and large enterprises that rely heavily on Java-based web infrastructure are particularly vulnerable. The lack of authentication or user interaction required for exploitation increases the risk of automated attacks. Additionally, prolonged service outages could affect compliance with service-level agreements and regulatory requirements. The vulnerability could also be leveraged as part of a multi-stage attack to distract or exhaust defenses while other malicious activities occur. Organizations with limited patch management capabilities or legacy systems are at higher risk.

1. Immediately upgrade Apache Tomcat to the fixed versions: 11.0.8, 10.1.42, or 9.0.106. 2. Implement resource usage monitoring and alerting on Tomcat servers to detect abnormal spikes in CPU, memory, or thread consumption. 3. Configure network-level protections such as rate limiting, web application firewalls (WAFs), and intrusion prevention systems (IPS) to limit the volume of requests to Tomcat services. 4. Review and tighten Tomcat connector and thread pool configurations to impose sensible limits on concurrent connections and resource allocation. 5. Conduct regular vulnerability scans and penetration tests focusing on resource exhaustion vectors. 6. For legacy or EOL Tomcat versions that cannot be immediately upgraded, consider isolating them behind reverse proxies or load balancers with strict traffic controls. 7. Maintain an incident response plan to quickly address potential denial of service incidents.