CVE-2023-26918: Understanding the Privilege Escalation Vulnerability in Diasoft File Replication Pro 7.5.

Recently, a privilege escalation vulnerability, associated with CVE-2023-26918, was identified in Diasoft File Replication Pro 7.5.. This vulnerability allows attackers to escalate privileges by replacing a legitimate file with a Trojan horse, which will be executed as LocalSystem. This post aims to provide an in-depth understanding of this vulnerability, including a code snippet, links to original references, and details about the exploit.

Code Snippet

The following code snippet demonstrates how the vulnerability is triggered due to the incorrect permission settings of %ProgramFiles%\FileReplicationPro, which allows Everyone:(F) access. This permission configuration enables any user on the system to replace the legitimate executable with a Trojan horse, leading to privilege escalation.

#include <Windows.h>
#include <tchar.h>

int _tmain(int argc, _TCHAR* argv[])
{
    TCHAR szInstallPath[MAX_PATH] = {};
    DWORD cchInstallPath = MAX_PATH;

    // Retrieve the installation path of FileReplicationPro
    _stprintf_s(szInstallPath, MAX_PATH, _T("%%ProgramFiles%%\\FileReplicationPro"));

    // Check if the directory exists
    if (GetFileAttributes(szInstallPath) != INVALID_FILE_ATTRIBUTES)
    {
        // If the directory exists, create a Trojan horse executable
        _tcscat_s(szInstallPath, MAX_PATH, _T("\\frpapp.exe"));
        CopyFile(_T("TrojanHorse.exe"), szInstallPath, FALSE);
    }

    return ;
}

Original References

The vulnerability was reported to the National Vulnerability Database (NVD) and is assigned CVE-2023-26918. You can view the original reference here. Additionally, below are several resources that provide more details about the vulnerability:

- Common Vulnerabilities and Exposures (CVE)
- CVE Details

Exploit Details

The exploitation of this vulnerability begins with the attacker gaining access to the system with low-privileged user rights. Once the attacker has access, they can replace any legitimate executable file, such as the "frpapp.exe" located in %ProgramFiles%\FileReplicationPro, with a Trojan horse that will be executed as LocalSystem. This is possible due to the incorrect permission set of the installation folder that allows access to all users.

Gain access to the targeted system with low-privileged user rights.

2. Replace the legitimate executable file within the %ProgramFiles%\FileReplicationPro directory with the Trojan horse that will exploit the weakness.
3. Wait for an unsuspecting user, typically with administrative privileges or a system service, to execute the malicious file.
4. Upon execution, the attacker's Trojan horse is launched with LocalSystem privileges, thereby escalating their rights on the system.

Conclusion

Understanding the vulnerability behind CVE-2023-26918 and its implications within Diasoft File Replication Pro 7.5. is essential for the security community. As a user of this software, it is crucial to be aware of potential risks and take necessary precautions. Ensure that your software is up-to-date and only deploy trustworthy applications to reduce the attack surface.

Through generating awareness and being proactive, we can lessen the likelihood of a successful escalation of privileges by attackers exploiting this vulnerability. Stay vigilant, and stay secure!

Timeline

Published on: 04/14/2023 00:15:00 UTC
Last modified on: 04/21/2023 20:00:00 UTC