CVE-2025-21521

Name of the Vulnerable Software and Affected Versions MySQL Server versions 8.0.39 and prior MySQL Server versions 8.4.2 and prior MySQL Server versions 9.0.1 and prior

Description The vulnerability in the MySQL Server product of Oracle MySQL, specifically in the Server: Thread Pooling component, can be exploited by an unauthenticated attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks can result in the unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. This issue is related to resource exhaustion, which can be triggered remotely.

Recommendations For MySQL Server versions 8.0.39 and prior, update to a version later than 8.0.39 to resolve the issue. For MySQL Server versions 8.4.2 and prior, update to a version later than 8.4.2 to resolve the issue. For MySQL Server versions 9.0.1 and prior, update to a version later than 9.0.1 to resolve the issue. As a temporary workaround, consider restricting network access to the MySQL Server to minimize the risk of exploitation.