# CVE-2017-3238: Oracle MySQL and MariaDB denial of service in Server Optimizer

Source: https://junglewise.ai/threats/cve-2017-3238-oracle-mysql-and-mariadb-denial-of-service-in-server-optimizer  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2017-01-27. Updated: 2026-05-13  
License: CC BY 4.0 with a link back

CVE-2017-3238 · Severity: medium · CVSS 6.5 · Published 2017-01-27

A vulnerability in the MySQL and MariaDB database servers could allow an attacker to crash the database service. This affects the Optimizer component, which is responsible for determining the most efficient way to execute SQL queries. An exploit could lead to a complete denial of service, causing applications relying on the database to become unavailable.

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

## Quick answers

**Is CVE-2017-3238 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2017-3238 being exploited in the wild.

**How severe is CVE-2017-3238?** Medium severity, with a CVSS score of 6.5, published 27 January 2017.

**Which products and versions are affected?** Oracle MySQL Server 5.5.53 and earlier, 5.6.34 and earlier, 5.7.16 and earlier.

**Is there a fix for CVE-2017-3238?** A patch was published on 2017-01-19: Debian released security update for mysql-5.5 (DSA 3767-1) Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2017-3238 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2017-3238?** Check whether you run Oracle MySQL Server 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 vulnerability is located in the 'Server: Optimizer' subcomponent of MySQL and MariaDB. It is classified as an 'easily exploitable' flaw that allows a low-privileged attacker with network access via multiple protocols to compromise the server's availability. The root cause is not publicly detailed beyond its location in the query optimizer, but the impact is a complete denial of service (hang or crash). The issue was addressed in MySQL versions 5.5.54, 5.6.35, and 5.7.17, and MariaDB versions 5.5.54, 10.0.29, and 10.1.21.

## Affected products

- Oracle MySQL Server 5.5.53 and earlier, 5.6.34 and earlier, 5.7.16 and earlier
- MariaDB Foundation MariaDB 5.5.0 to 5.5.53, 10.0.0 to 10.0.28, 10.1.0 to 10.1.20

## Timeline

- 2017-01-17: advisory: Oracle Critical Patch Update (CPU) released
- 2017-01-19: patched: Debian released security update for mysql-5.5 (DSA 3767-1)
- 2017-01-22: patched: Debian released security update for mariadb-10.0 (DSA 3770-1)
- 2017-01-27: disclosed: NVD publication date

## References

- [http://www.debian.org/security/2017/dsa-3767](http://www.debian.org/security/2017/dsa-3767)
- [http://www.debian.org/security/2017/dsa-3770](http://www.debian.org/security/2017/dsa-3770)
- [http://www.oracle.com/technetwork/security-advisory/cpujan2017-2881727.html](http://www.oracle.com/technetwork/security-advisory/cpujan2017-2881727.html)
- [http://www.securityfocus.com/bid/95571](http://www.securityfocus.com/bid/95571)
- [http://www.securitytracker.com/id/1037640](http://www.securitytracker.com/id/1037640)
- [https://access.redhat.com/errata/RHSA-2017:2192](https://access.redhat.com/errata/RHSA-2017:2192)
- [https://access.redhat.com/errata/RHSA-2017:2787](https://access.redhat.com/errata/RHSA-2017:2787)

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