CVE-2025-48924 is a vulnerability classified under CWE-674 (Uncontrolled Recursion) affecting the Apache Commons Lang library, a widely used Java utility library. The flaw exists in the ClassUtils.getClass(...) method across versions 2.0 to 2.6 and 3.0 up to before 3.18.0. When this method processes very long or maliciously crafted input strings, it can enter uncontrolled recursion, leading to a StackOverflowError. Unlike typical exceptions, StackOverflowError is an Error subclass in Java, which many applications and libraries do not catch or handle properly. Consequently, this error can cause the Java Virtual Machine (JVM) thread to terminate abruptly, leading to application crashes or denial of service (DoS). The vulnerability is remotely exploitable without authentication or user interaction, as it only requires the attacker to supply crafted input to the affected method. The CVSS v3.1 base score is 5.3, reflecting a medium severity primarily due to availability impact, with no confidentiality or integrity compromise. No known exploits have been reported in the wild yet. The recommended remediation is to upgrade Apache Commons Lang to version 3.18.0 or later, where the recursion issue has been fixed. This vulnerability is particularly relevant for enterprise Java applications that rely on Commons Lang for reflection and class loading utilities, especially those exposed to untrusted input or external interfaces.

For European organizations, the primary impact of CVE-2025-48924 is the potential for denial of service caused by application crashes due to unhandled StackOverflowError exceptions. This can disrupt business-critical Java applications, leading to downtime, degraded service availability, and potential operational losses. Since the vulnerability does not affect confidentiality or integrity, data breaches or unauthorized data modification are unlikely. However, availability issues can affect customer-facing services, internal workflows, and automated systems relying on Java applications using the vulnerable Commons Lang versions. Organizations in sectors such as finance, telecommunications, government, and software development—where Java is prevalent—may experience service interruptions if exploited. The lack of required authentication and user interaction means attackers can remotely trigger the vulnerability, increasing risk especially for applications exposed to the internet or untrusted networks. Although no exploits are currently known in the wild, the medium severity and ease of triggering the issue warrant proactive mitigation to avoid potential service disruptions.

1. Upgrade Apache Commons Lang to version 3.18.0 or later immediately, as this version contains the fix for the uncontrolled recursion issue. 2. Conduct an inventory of all Java applications and services to identify usage of affected Commons Lang versions (2.0 to 2.6 and 3.0 to before 3.18.0). 3. For applications where immediate upgrade is not feasible, implement input validation and sanitization to limit input length and prevent maliciously crafted inputs from reaching ClassUtils.getClass(...). 4. Employ runtime monitoring and alerting for StackOverflowError occurrences to detect potential exploitation attempts early. 5. Use application-layer firewalls or web application firewalls (WAFs) to filter suspicious or abnormally long input parameters targeting affected services. 6. Review and enhance exception handling in Java applications to gracefully handle Errors where possible, minimizing service impact. 7. Test patched applications thoroughly in staging environments before production deployment to ensure stability. 8. Maintain up-to-date software inventories and vulnerability management processes to quickly respond to similar future issues.