CVE-2025-21518

Name of the Vulnerable Software and Affected Versions MySQL Server versions 8.0.40 and prior MySQL Server versions 8.4.3 and prior MySQL Server versions 9.1.0 and prior

Description The issue is related to an unbounded resource allocation in the MySQL Server product, specifically in the Server: Optimizer component. This can be exploited by a remote attacker with low privileges and network access via multiple protocols, potentially leading to a denial of service (DOS) by causing the MySQL Server to hang or crash repeatedly. The estimated impact is on the availability of the system.

Recommendations For MySQL Server versions 8.0.40 and prior, update to a version later than 8.0.40 to resolve the issue. For MySQL Server versions 8.4.3 and prior, update to a version later than 8.4.3 to resolve the issue. For MySQL Server versions 9.1.0 and prior, update to a version later than 9.1.0 to resolve the issue. As a temporary workaround, consider restricting network access to the MySQL Server to minimize the risk of exploitation.