# CVE-2026-101781: Oracle MySQL Server and MySQL Cluster unauthenticated network compromise in Group Replication GCS

Source: https://junglewise.ai/threats/cve-2026-101781-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-2026-101781 · Severity: high · CVSS 8.8 · Published 2026-10-20

Oracle MySQL Server and MySQL Cluster are widely used database systems that store and manage critical business data. A vulnerability in the Group Replication component allows an attacker on the same physical network segment to take complete control of a MySQL database server without requiring credentials, potentially exposing, modifying, or destroying all stored data.

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-2026-101781 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-101781 being exploited in the wild.

**How severe is CVE-2026-101781?** High severity, with a CVSS score of 8.8, 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-2026-101781?** 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-2026-101781 attacked?** It is attacked from the adjacent network, in a hosted service.

**Am I affected by CVE-2026-101781?** 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

An easily exploitable vulnerability in the Server: Group Replication GCS component allows unauthenticated attackers with adjacent network access (on the same physical communication segment) to achieve complete system compromise. The attack requires no authentication, user interaction, or special privileges; successful exploitation results in full takeover of the MySQL Server or Cluster instance. The vulnerability is addressed in patched versions of both MySQL Server and MySQL Cluster.

## 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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