A recently discovered vulnerability known as CVE-2022-27448 has raised security concerns within the web community, as it affects MariaDB Server version 10.9 and below. This vulnerability stems from an Assertion failure in node->pcur->rel_pos == BTR_PCUR_ON located at /row/rowmysql.cc. This post aims to provide a comprehensive analysis of this vulnerability, including code snippets, original references, and a detailed overview of the exploit.

Background

MariaDB is a popular open-source relational database management system (RDBMS) that is widely used for web applications due to its flexibility, scalability, and ease of use. However, like any complex software system, it can contain bugs and vulnerabilities that may be exploited by cybercriminals to compromise servers and steal sensitive data.

The Vulnerability: CVE-2022-27448

CVE-2022-27448 is a critical vulnerability in MariaDB Server that causes an assertion failure, potentially leading to a crash or other unpredictable behavior. This vulnerability resides in the row/rowmysql.cc file, specifically in the line where the node->pcur->rel_pos is checked against BTR_PCUR_ON.

The following code snippet from the affected file showcases the vulnerable line

if (node->pcur->rel_pos == BTR_PCUR_ON) {
    ut_a(node->pcur->rel_pos == BTR_PCUR_ON);
}

This issue occurs when the provided relational position (node->pcur->rel_pos) does not match with the expected position (BTR_PCUR_ON). The result is an Assertion failure, which can lead to unpredictable behavior within the MariaDB Server.

Exploit Details

A skilled attacker could exploit this vulnerability by crafting a malicious SQL query that abuses the improper handling of relational positions within the row/rowmysql.cc file. By causing an assertion failure, the attacker could potentially crash the MariaDB Server, leading to a denial-of-service (DoS) attack. In the worst-case scenario, this vulnerability may allow an attacker to execute arbitrary code, providing them unauthorized access to the server and the sensitive data stored within.

It is crucial to note that this vulnerability can only be exploited if the attacker already has access to the MariaDB Server, and the impact may vary depending on the server configuration and permissions granted to the attacker.

Original References

For more information regarding CVE-2022-27448, the MariaDB Server issue tracker provides the following resources:

1. MariaDB Server Jira Issue MDEV-27831 – This is the official Jira issue tracking the vulnerability and its progress towards a fix.
2. MariaDB Server Github Repository – This is the official Github repository where the source code for MariaDB Server can be found and analyzed.

Available Patches

MariaDB Server developers have been quick to respond to this vulnerability, and a patch has already been released to address the issue. Users are strongly advised to update their MariaDB Server installations to the latest version, which contains the necessary bug fixes to prevent exploitation.

The specific patch addressing CVE-2022-27448 can be found here.

Conclusion

CVE-2022-27448 is a critical vulnerability affecting MariaDB Server version 10.9 and below. By exploiting this assertion failure, an attacker could potentially crash the MariaDB Server, execute arbitrary code, or gain unauthorized access to a system. To protect against this vulnerability, users should update their MariaDB Server installations to the latest patched version.

Timeline

Published on: 04/14/2022 13:15:00 UTC
Last modified on: 05/26/2022 08:15:00 UTC