CVE-2025-24497 in BIG-IP
Summary
by MITRE • 02/05/2025
When URL categorization is configured on a virtual server, undisclosed requests can cause TMM to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
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Analysis
by VulDB Data Team • 08/06/2025
This vulnerability exists within F5 Big-IP application delivery controllers where the Traffic Management Microkernel (TMM) process terminates unexpectedly when handling certain undisclosed requests on virtual servers configured with URL categorization. The issue stems from improper handling of specific request patterns that trigger a memory corruption or resource management failure within the TMM component. When these malformed or unexpected requests are processed through the URL categorization functionality, the system exhibits a critical failure mode that results in complete process termination. The vulnerability specifically affects systems where URL categorization is enabled on virtual servers, making it particularly relevant for organizations implementing web content filtering or security policies through F5 appliances.
The technical flaw manifests as a lack of proper input validation and error handling within the TMM's request processing pipeline when URL categorization is active. The undisclosed nature of the specific request patterns suggests that the vulnerability may be triggered by malformed HTTP headers, unusual URL structures, or unexpected content that causes the TMM to attempt operations beyond its intended processing boundaries. This type of vulnerability aligns with CWE-248, which covers "Uncaught Exception" conditions, and may also relate to CWE-121, "Stack-based Buffer Overflow", if the termination occurs due to memory corruption. The TMM process termination represents a denial of service condition that can be exploited by remote attackers to disrupt service availability on affected systems.
The operational impact of this vulnerability is significant as it can lead to complete service disruption on F5 Big-IP appliances where URL categorization is implemented. Organizations relying on web filtering capabilities through F5 appliances may experience unexpected service outages, particularly when dealing with malicious or malformed requests that trigger the termination. The vulnerability affects systems that have not reached end of technical support, meaning current customers with active support contracts remain at risk. This represents a critical security concern for enterprises that depend on F5 appliances for application delivery and security services, as the denial of service can be both intentional and unintentional, potentially affecting legitimate users and business operations. The issue can be particularly problematic in environments where high availability and continuous service delivery are required.
Mitigation strategies should focus on applying the latest security patches provided by F5, which typically address the underlying memory handling and input validation issues within the TMM component. Organizations should also implement network-level controls to filter and sanitize requests before they reach the vulnerable virtual servers, particularly when URL categorization is active. Monitoring and logging should be enhanced to detect unusual patterns that may precede the termination events, enabling proactive response measures. Network segmentation and access controls can help limit the potential impact by restricting access to vulnerable virtual servers. Additionally, implementing redundant systems or failover mechanisms can help maintain service availability during patch deployment or when immediate remediation is not possible, aligning with ATT&CK technique T1499.004 for "Fork Bomb" and similar denial of service patterns that can be mitigated through proper system hardening and monitoring practices.