CVE-2026-34270: Medium severity Oracle MySQL Server vulnerability
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Group Replication Plugin). Supported versions that are affected are 8.0.0-8.0.45, 8.4.0-8.4.8 and 9.0.0-9.6.0. 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 3.1 Base Score 6.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H).
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Remove
Remove
MySQL Server: Group Replication Pluginfrom your environment.Uninstall or remove the Group Replication Plugin from MySQL Server instances where it is not required.
- Configuration
Disable the Group Replication Plugin on affected MySQL Server instances if group replication is not required to prevent exploitation of the vulnerability.
MySQL Server (Group Replication Plugin) group_replication = disabled - Compensating control
Restrict network access to MySQL Server (and services exposing the Group Replication Plugin) to trusted hosts/IPs and networks via firewall, ACLs or network segmentation to prevent untrusted remote access over the multiple protocols noted.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-34270?
CVE-2026-34270 has a high severity rating due to its potential for exploitation by low privileged attackers.
How do I fix CVE-2026-34270?
To fix CVE-2026-34270, upgrade your MySQL Server to a version that is not affected, such as versions higher than 8.0.45, 8.4.8, or 9.6.0.
Who is affected by CVE-2026-34270?
CVE-2026-34270 affects users of MySQL Server versions 8.0.0 through 8.0.45, 8.4.0 through 8.4.8, and 9.0.0 through 9.6.0.
What types of attacks can exploit CVE-2026-34270?
CVE-2026-34270 can be exploited through network access by low privileged attackers using multiple protocols.
Is there a patch available for CVE-2026-34270?
Yes, patches for CVE-2026-34270 are included in the updated MySQL Server versions that users are encouraged to upgrade to.