CVE-2026-22009 Oracle Corporation CVE debrief

Who should care

MySQL Server administrators, security teams, and IT professionals responsible for maintaining and securing MySQL Server instances should assess exposure and apply patches or updates as needed.

Why it matters

CVE-2026-22009 is a medium-severity vulnerability in MySQL Server's Optimizer component that allows low-privileged attackers to cause a hang or crash of the MySQL Server, resulting in a Denial of Service (DOS). MySQL Server administrators and security teams should assess exposure and apply patches or updates as needed to prevent potential DOS and ensure database availability.

• Potential Denial of Service (DOS) due to MySQL Server crashes
• Need to verify exposure of MySQL Server instances to this vulnerability
• Requirement to assess and apply patches or updates to affected versions
• Potential impact on database availability and business operations

Technical summary

The vulnerability affects MySQL Server versions 8.0.0-8.0.45, 8.4.0-8.4.8, and 9.0.0-9.6.0. A low-privileged attacker with network access can exploit this vulnerability to cause a hang or crash of the MySQL Server, resulting in a Denial of Service (DOS). The CVSS score is 6.5 (Medium severity). This vulnerability is in the Optimizer component of 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. MySQL Server administrators and security teams should assess exposure and apply patches or updates as needed.

Defensive priority

Medium priority for MySQL Server administrators and security teams to assess exposure and apply patches.

Recommended defensive actions

• Assess exposure of MySQL Server instances to this vulnerability
• Apply patches or updates to affected versions
• Monitor MySQL Server logs for potential attacks
• Review network access controls to limit low-privileged attacker access
• Verify MySQL Server instances are up-to-date and patched
• Track exceptions and retest remediated assets
• Review compensating controls for exposed systems while remediation is scheduled and verified

Evidence notes

The CVE record and NVD detail page provide information on the vulnerability, affected versions, and CVSS score. The vulnerability allows low-privileged attackers with network access to cause a hang or crash of the MySQL Server, resulting in a Denial of Service (DOS). The CVSS score is 6.5 (Medium severity). MySQL Server administrators and security teams should assess exposure and apply patches or updates as needed. The CVE record was published on 2026-04-21T21:16:27.353Z and has not been modified since then. The NVD detail page and 3

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.