Oracle MySQL Server up to 8.0.39/8.4.2/9.0.1 Thread Pooling improper authentication

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Oracle MySQL Server up to 8.0.39/8.4.2/9.0.1 and classified as critical. This affects an unknown function of the component Thread Pooling. Executing a manipulation can lead to improper authentication. This vulnerability appears as CVE-2025-21521. The attack may be performed from remote. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Oracle MySQL Server up to 8.0.39/8.4.2/9.0.1 and classified as critical. This vulnerability affects an unknown code of the component Thread Pooling. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect availability. CVE summarizes:

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).

The advisory is shared for download at oracle.com. This vulnerability was named CVE-2025-21521 since 12/25/2024. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 216473 (RHEL 9 : mysql (RHSA-2025:1671)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (216473) and CERT Bund (WID-SEC-2025-0167). Once again VulDB remains the best source for vulnerability data.

Affected

  • Oracle MySQL
  • Debian Linux
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • NetApp ActiveIQ Unified Manager
  • RESF Rocky Linux
  • MariaDB MariaDB

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (oracle): 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 216473
Nessus Name: RHEL 9 : mysql (RHSA-2025:1671)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/25/2024 🔍
01/21/2025 +27 days 🔍
01/21/2025 +0 days 🔍
01/09/2026 +353 days 🔍

Sourcesinfo

Vendor: oracle.com

Advisory: oracle.com
Status: Confirmed

CVE: CVE-2025-21521 (🔍)
GCVE (CVE): GCVE-0-2025-21521
GCVE (VulDB): GCVE-100-292828
CERT Bund: WID-SEC-2025-0167 - Oracle MySQL: Mehrere Schwachstellen

Entryinfo

Created: 01/21/2025 22:44
Updated: 01/09/2026 13:01
Changes: 01/21/2025 22:44 (64), 02/19/2025 17:39 (2), 01/09/2026 13:01 (7)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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