CVE-2025-21543 - Vulnerability in MySQL Server Product Allows High Privileged Attacker to Cause Complete DoS

CVE-2025-21543 is a security vulnerability discovered in the MySQL Server product of Oracle MySQL. The affected component is the Server: Packaging, and it affects the following supported versions - 8..40 and prior, 8.4.3 and prior, and 9.1. and prior. The vulnerability allows a high privileged attacker with network access via multiple protocols to compromise the MySQL Server and gain unauthorized ability to cause a hang or frequently repeatable crash (complete Denial of Service (DoS)) of the server. The CVSS 3.1 Base Score for this vulnerability is 4.9, and the CVSS Vector is (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).

In this post, we will discuss the details of this vulnerability, including the code snippet, original references, and exploit information.

Code Snippet

The vulnerability lies in the Server: Packaging component of the affected MySQL Server product. Currently, there is no public code snippet available that demonstrates the exploitation. However, the vulnerability may involve the attacker sending a specially crafted request to the MySQL server that, when processed, causes a crash or hang of the server.

Original References

The CVE-2025-21543 vulnerability was first reported by Oracle and later added to the CVE List by the MITRE Corporation. The following links provide additional information about this specific vulnerability:

1. Oracle Security Advisory: https://www.oracle.com/security-alerts/cpuoct2025.html
2. CVE Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-21543
3. National Vulnerability Database (NVD): https://nvd.nist.gov/vuln/detail/CVE-2025-21543

Exploit Details

As mentioned earlier, the vulnerability allows a high privileged attacker to cause a DoS (Denial of Service) attack on the MySQL server. This can be achieved by sending specially crafted requests to the server and exploiting the vulnerability within the Server: Packaging component.

The following steps outline a possible exploitation scenario

1. The attacker identifies the target MySQL Server and recognizes that it is running one of the vulnerable versions (8..40 and prior, 8.4.3 and prior, or 9.1. and prior).

2. The attacker crafts a malicious request that triggers the vulnerability within the Server: Packaging component of the MySQL server.

3. The attacker sends the specially crafted request to the target server using their high-level privileges.

4. Upon receiving the malicious request, the targeted MySQL Server experiences a hang or frequently repeatable crash, causing a complete DoS situation.

It is essential to note that no public proof-of-concept (PoC) or exploit code for CVE-2025-21543 exists at the time of writing. The information provided is based on the description of the vulnerability and the possible impact scenarios.

Conclusion

The CVE-2025-21543 vulnerability in the MySQL Server product of Oracle MySQL poses a serious threat to organizations relying on vulnerable versions of the server. High privileged attackers have the potential to compromise server availability severely, leading to substantial downtime and interruption of critical services.

To protect against this vulnerability, it is crucial for administrators to update their MySQL Server instances to the latest patched versions available from Oracle. Additionally, organizations should employ strict access control mechanisms to limit the number of high privileged users on their network, reducing potential entry points for an attacker.

Timeline

Published on: 01/21/2025 21:15:20 UTC
Last modified on: 01/22/2025 19:15:13 UTC