CVE-2021-2389: MySQL memcached Plugin Integer Underflow Remote Code Execution Vulnerability

Published Jul 20, 2021
·
Updated

This vulnerability allows remote attackers to execute arbitrary code on affected installations of MySQL. Authentication is not required to exploit this vulnerability. The specific flaw exists within the processing of Append and Prepend commands in the memcached plugin. The issue results from the lack of proper validation of user-supplied data, which can result in an integer underflow before writing to memory. An attacker can leverage this vulnerability to execute code in the context of the service account.

Other sources

Vulnerability in the MySQL Server product of Oracle MySQL (component: InnoDB). Supported versions that are affected are 5.7.34 and prior and 8.0.25 and prior. Difficult to exploit vulnerability allows unauthenticated 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.

External References:

http://www.oracle.com/security-alerts/cpujul2021.html#AppendixMSQL

Red Hat

Vulnerability in the MySQL Server product of Oracle MySQL (component: InnoDB). Supported versions that are affected are 5.7.34 and prior and 8.0.25 and prior. Difficult to exploit vulnerability allows unauthenticated 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 5.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).

MITRE

Affected Software

22 affected componentsFixes available
redhat/mysql<5.7.35
5.7.35
redhat/mysql<8.0.26
8.0.26
redhat/mariadb<10.6.4
10.6.4
redhat/mariadb<10.5.12
10.5.12
redhat/mariadb<10.4.21
10.4.21
redhat/mariadb<10.3.31
10.3.31
redhat/mariadb<10.2.40
10.2.40
Oracle MySQL
Oracle MySQL Server>=5.7.0<=5.7.34
Oracle MySQL Server>=8.0.0<=8.0.25
NetApp Active Iq Unified Manager Vmware Vsphere
NetApp Active Iq Unified Manager Windows
NetApp OnCommand Insight
NetApp OnCommand Workflow Automation
NetApp Snapcenter
Fedoraproject Fedora=34
Fedoraproject Fedora=35
MariaDB MariaDB>=10.2.0<10.2.40
MariaDB MariaDB>=10.3.0<10.3.31
MariaDB MariaDB>=10.4.0<10.4.21
MariaDB MariaDB>=10.5.0<10.5.12
MariaDB MariaDB>=10.6.0<10.6.4

Event History

Jul 20, 2021
CVE Published
via MITRE·10:44 PM
Data Sourced
via MITRE·10:44 PM
DescriptionSeverityWeakness
Mar 25, 2025
Advisory Published
via ZDI·02:26 AM
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Frequently Asked Questions

1

What is the severity of CVE-2021-2389?

CVE-2021-2389 is classified as a difficult-to-exploit vulnerability that allows unauthenticated network access.

2

How do I fix CVE-2021-2389?

To resolve CVE-2021-2389, upgrade MySQL Server to version 5.7.35 or 8.0.26, or update MariaDB to version 10.6.4, 10.5.12, 10.4.21, 10.3.31, or 10.2.40.

3

Which MySQL versions are affected by CVE-2021-2389?

CVE-2021-2389 affects MySQL Server versions 5.7.34 and prior, as well as 8.0.25 and prior.

4

What types of network access could exploit CVE-2021-2389?

CVE-2021-2389 can potentially be exploited via multiple network protocols within unauthorized access scenarios.

5

Are there any specific configurations that mitigate CVE-2021-2389?

Mitigation efforts for CVE-2021-2389 primarily involve updating to the recommended versions of MySQL and MariaDB.

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