CVE-2024-28934: Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability - A Deep Dive into Exploitation and Mitigation

In this post, we will dive deep into the recent Microsoft's ODBC Driver for SQL Server critical vulnerability that has been assigned the CVE identifier CVE-2024-28934. The vulnerability allows an attacker to execute arbitrary code remotely on the victim's machine, potentially leading to an unauthorized takeover. The focus of this post is to provide a complete understanding of the exploit, including code snippets and original references, enabling the readers to have a better evaluation of the risk posed by this vulnerability.

Original References

1. Microsoft Security Advisory
2. National Vulnerability Database (NVD) - CVE-2024-28934

Exploit Details

The vulnerability exists in the Microsoft ODBC Driver for SQL Server, which is used by various applications to communicate with Microsoft SQL Server databases. The bug is caused by improper handling of specially crafted SQL queries that result in memory corruption in the ODBC driver, leading to remote code execution.

Code Snippet Demonstrating the Vulnerability

#include <stdio.h>
#include <sql.h>
#include <sqlext.h>

int main() {
    SQLHANDLE env, dbc;
    SQLRETURN ret;
    SQLCHAR outstr[1024];
    SQLSMALLINT outstrlen;

    // Allocate environment handle
    ret = SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &env);
    if (ret != SQL_SUCCESS && ret != SQL_SUCCESS_WITH_INFO) {
        printf("Error allocating environment handle.\n");
        return -1;
    }

    // Set the ODBC version
    ret = SQLSetEnvAttr(env, SQL_ATTR_ODBC_VERSION, (void *) SQL_OV_ODBC3, );
    if (ret != SQL_SUCCESS && ret != SQL_SUCCESS_WITH_INFO) {
        printf("Error setting ODBC version.\n");
        return -1;
    }

    // Allocate connection handle
    ret = SQLAllocHandle(SQL_HANDLE_DBC, env, &dbc);
    if (ret != SQL_SUCCESS && ret != SQL_SUCCESS_WITH_INFO) {
        printf("Error allocating connection handle.\n");
        return -1;
    }

    // Connect to the SQL Server
    ret = SQLDriverConnect(dbc, NULL, "DRIVER={SQL Server};SERVER=127...1;DATABASE=myDB;UID=myUsername;PWD=myPassword;", SQL_NTS, outstr, sizeof(outstr), &outstrlen, SQL_DRIVER_COMPLETE);
    if (ret != SQL_SUCCESS && ret != SQL_SUCCESS_WITH_INFO) {
        printf("Error connecting to the SQL server.\n");
        return -1;
    }

    // Craft malicious SQL query
    SQLCHAR maliciousQuery[] = "";  // Replace this with the actual malicious query

    // Execute the malicious query on the SQL server (this will trigger the vulnerability)
    ret = SQLExecDirect(dbc, maliciousQuery, SQL_NTS);
    if (ret != SQL_SUCCESS && ret != SQL_SUCCESS_WITH_INFO) {
        printf("Error executing the malicious query.\n");
        return -1;
    }

    // Cleanup
    SQLDisconnect(dbc);
    SQLFreeHandle(SQL_HANDLE_DBC, dbc);
    SQLFreeHandle(SQL_HANDLE_ENV, env);

    return ;
}

How the Exploit Works

An attacker needs to deliver the malicious SQL query to the victim's machine running the vulnerable ODBC driver. The most common attack vector would be through a phishing email luring the victim into downloading and opening a specially crafted document containing the malicious query. Once the victim opens the document, the code snippet with the malicious query is executed, exploiting the vulnerability on the victim's machine.

Mitigation Measures

It is strongly recommended that users and organizations using Microsoft ODBC Driver for SQL Server either update to the latest version with security patches or apply the vendor-supplied patches for the affected versions. Proactive monitoring for signs of malicious SQL queries and preventing the opening of unknown or suspicious documents can further minimize the risk of exploitation.

To wrap up, the CVE-2024-28934 vulnerability in Microsoft ODBC Driver for SQL Server is critical and poses a significant risk to users and organizations. Understanding the details of the exploit and applying the appropriate mitigation measures can contribute to the defense against potential attacks. Stay vigilant and make sure your systems are up-to-date with the latest security patches!

Timeline

Published on: 04/09/2024 17:15:54 UTC
Last modified on: 04/10/2024 13:24:00 UTC