# CVE-2026-101776: Oracle MySQL Server Group Replication Plugin denial of service

Source: https://junglewise.ai/threats/cve-2026-101776-vulnerability-in-the-mysql-server-mysql-cluster-product-of  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-20. Updated: 2026-10-20  
License: CC BY 4.0 with a link back

CVE-2026-101776 · Severity: medium · CVSS 4.9 · Published 2026-10-20

Oracle MySQL Server and MySQL Cluster use a Group Replication Plugin to coordinate database replicas across a cluster. A high-privileged attacker with network access can trigger a bug in this plugin that causes the database to hang or crash repeatedly, resulting in a complete denial of service. This vulnerability affects multiple versions of both MySQL Server and MySQL Cluster across the 8.0, 8.4, 9.7, and 26.7 release branches.

Technologies: [Oracle MySQL Server](https://junglewise.ai/threats/technologies/mysql-server), [Oracle Mysql Cluster](https://junglewise.ai/threats/technologies/mysql-cluster). Vendors: [Oracle](https://junglewise.ai/threats/vendors/oracle).

## Quick answers

**Is CVE-2026-101776 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-101776 being exploited in the wild.

**How severe is CVE-2026-101776?** Medium severity, with a CVSS score of 4.9, published 20 October 2026.

**Which products and versions are affected?** Oracle MySQL Server 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1; Oracle Mysql Cluster 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1.

**Is there a fix for CVE-2026-101776?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-101776 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-101776?** Check whether you run Oracle MySQL Server or Oracle Mysql Cluster at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

This is a denial-of-service vulnerability in the MySQL Server Group Replication Plugin component. The vulnerability requires high privileges and network access via multiple protocols, but allows an attacker to cause a hang or repeatedly crash the database server, resulting in unavailability. The attack has no impact on confidentiality or integrity, only on availability.

## Affected products

- Oracle MySQL Server 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1
- Oracle MySQL Cluster 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1

## Timeline

- 2026-10-20: disclosed

## References

- [https://www.oracle.com/security-alerts/cpuoct2026.html](https://www.oracle.com/security-alerts/cpuoct2026.html)

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