# CVE-2017-3251: Oracle MySQL Server denial of service in Optimizer

Source: https://junglewise.ai/threats/cve-2017-3251-oracle-mysql-server-denial-of-service-in-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-2017-3251 · Severity: medium · CVSS 4.9 · Published 2017-01-27

A vulnerability in the Optimizer component of Oracle MySQL Server allows a high-privileged user to remotely crash the database. This can lead to a complete denial of service, impacting business operations that rely on the database's availability. Successful exploitation results in a server hang or a repeatable crash, requiring administrative intervention to restore service.

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

## Quick answers

**Is CVE-2017-3251 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2017-3251 being exploited in the wild.

**How severe is CVE-2017-3251?** Medium severity, with a CVSS score of 4.9, published 27 January 2017.

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

**Is there a fix for CVE-2017-3251?** A patch was published on 2017-10-12: Red Hat released updates for rh-mysql57-mysql (5.7.19) Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2017-3251 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2017-3251?** Check whether you run Oracle Mysql or 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

An unspecified vulnerability exists in the Server: Optimizer subcomponent of Oracle MySQL Server versions 5.7.16 and earlier. The flaw is easily exploitable by a high-privileged attacker with network access via multiple protocols. Successful exploitation allows the attacker to cause a hang or a frequently repeatable crash of the MySQL Server, resulting in a complete denial of service (DoS). The vulnerability was addressed in the Oracle Critical Patch Update for January 2017, with fixes included in MySQL version 5.7.17 and later.

## Affected products

- Oracle MySQL Server 5.7.16 and earlier

## Timeline

- 2017-01-27: advisory: Initial publication of CVE-2017-3251 by Oracle
- 2017-10-12: patched: Red Hat released updates for rh-mysql57-mysql (5.7.19)

## References

- [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/95482](http://www.securityfocus.com/bid/95482)
- [http://www.securitytracker.com/id/1037640](http://www.securitytracker.com/id/1037640)
- [https://access.redhat.com/errata/RHSA-2017:2886](https://access.redhat.com/errata/RHSA-2017:2886)
- [https://security.gentoo.org/glsa/201702-17](https://security.gentoo.org/glsa/201702-17)

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