CVE-2025-21521: High severity Oracle MySQL Server vulnerability

Published Jan 21, 2025
·
Updated

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Thread Pooling). Supported versions that are affected are 8.0.39 and prior, 8.4.2 and prior and 9.0.1 and prior. Easily exploitable 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 7.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Affected Software

5 affected componentsFixes available
Oracle MySQL Server<8.0.39, <8.4.2, <9.0.1
Oracle MySQL Server>=8.0.0<=8.0.39
Oracle MySQL Server>=8.4.0<=8.4.2
Oracle MySQL Server>=9.0.0<=9.0.1
Microsoft azl3 mysql 8.0.41-1<8.0.40-1
8.0.40-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.0.40-1
  2. Upgrade

    Upgrade Oracle MySQL (Server: Thread Pooling) to a version that resolves this vulnerability.

    Fixed in 8.0.39
  3. Upgrade

    Upgrade Oracle MySQL (Server: Thread Pooling) to a version that resolves this vulnerability.

    Fixed in 8.4.2
  4. Upgrade

    Upgrade Oracle MySQL (Server: Thread Pooling) to a version that resolves this vulnerability.

    Fixed in 9.0.1

Event History

Jan 21, 2025
CVE Published
via MITRE·08:53 PM
Data Sourced
via MITRE·08:53 PM
DescriptionSeverity
Data Sourced
via Red Hat·09:05 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software
Sep 4, 2025
Data Sourced
via Microsoft·05:13 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·05:13 AM
Affected Software
Updated
via Microsoft·05:13 AM
DescriptionSeverity

Frequently Asked Questions

1

What is the severity of CVE-2025-21521?

CVE-2025-21521 is considered an easily exploitable vulnerability that allows unauthorized access, impacting the security of MySQL Server.

2

How do I fix CVE-2025-21521?

To fix CVE-2025-21521, upgrade to MySQL Server versions 8.0.40, 8.4.3, or 9.0.2 or later.

3

Which MySQL Server versions are affected by CVE-2025-21521?

The affected MySQL Server versions include 8.0.39 and prior, 8.4.2 and prior, and 9.0.1 and prior.

4

Who is affected by CVE-2025-21521?

Organizations using affected versions of MySQL Server may be vulnerable to attacks due to CVE-2025-21521.

5

Can CVE-2025-21521 be exploited remotely?

Yes, CVE-2025-21521 can be exploited by unauthenticated attackers with network access via multiple protocols.

Contact

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