CSIRTS // UNIFIED SECURITY ADVISORY FEEDSYS ● ONLINE · POWERED BY INTELFUSIONS.COM

← Back to feed

CVE-2025-21500: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.40 and prior, 8.4.3 and prior and 9.1.0 and prior. Easily exploitable vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS

mediumCVSS 6.5CVE-2025-21500

CSIRTS triage

vendor: Oracleproduct: MySQL ServerOtheraffected: 8.0.40 and prior, 8.4.3 and prior, 9.1.0 and prior
What
Vulnerability in the Optimizer component of MySQL Server allows a low-privileged attacker with network access to cause unspecified impact.
Who is affected
Oracle MySQL deployments on all affected versions with network-exposed instances.
Urgency
Medium severity (CVSS 6.5); easily exploitable by low-privileged network users.
Action
Update MySQL Server to a patched version addressing CVE-2025-21500.

AI-assisted analysis generated from the source advisory — verify against the original.

⚡ Watch MySQL Server

Get an email when a new MySQL Server advisory drops — max one per day, one-click unsubscribe.

Details

Source
Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity
medium — CVSS 6.5
Published
2026-08-06
Exploitation
Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21500

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Referenced CVEs

CVECSIRTS overviewExternal
CVE-2025-21500coverage & exploitation statusNVD · CVE.org

More from Microsoft Security Response Center