CVE-2018-6856 Explained : Impact and Mitigation

Sophos SafeGuard Enterprise, SafeGuard Easy, and SafeGuard LAN Crypt versions prior to specific releases contain a vulnerability allowing Local Privilege Escalation through IOCTL 0x8020601C.

Understanding CVE-2018-6856

This CVE involves a security flaw in Sophos SafeGuard products that can be exploited for Local Privilege Escalation.

What is CVE-2018-6856?

Versions of Sophos SafeGuard Enterprise before 8.00.5, SafeGuard Easy before 7.00.3, and SafeGuard LAN Crypt before 3.95.2 are susceptible to a Local Privilege Escalation vulnerability via IOCTL 0x8020601C. Attackers can manipulate the execution path to write to user-controlled addresses, potentially leading to code execution as SYSTEM.

The Impact of CVE-2018-6856

This vulnerability allows attackers to escalate privileges locally, potentially compromising the security of affected systems and executing unauthorized code.

Technical Details of CVE-2018-6856

Sophos SafeGuard products are vulnerable to Local Privilege Escalation through a specific IOCTL manipulation.

Vulnerability Description

By crafting an input buffer, attackers can control the execution path to write to user-controlled addresses, enabling the execution of code within the context of a privileged process.

Affected Systems and Versions

Sophos SafeGuard Enterprise versions prior to 8.00.5
SafeGuard Easy versions prior to 7.00.3
SafeGuard LAN Crypt versions prior to 3.95.2

Exploitation Mechanism

Attackers carefully construct an input buffer to manipulate the execution path.
This manipulation allows writing to addresses controlled by the user, facilitating privilege escalation and potential code execution.

Mitigation and Prevention

Steps to address and prevent the CVE-2018-6856 vulnerability.

Immediate Steps to Take

Update Sophos SafeGuard products to versions 8.00.5, 7.00.3, and 3.95.2 or later.
Monitor system activity for any signs of unauthorized privilege escalation attempts.

Long-Term Security Practices

Regularly update and patch all software to mitigate potential vulnerabilities.
Implement least privilege access controls to limit the impact of privilege escalation attacks.
Conduct security training to educate users on identifying and reporting suspicious activities.

Patching and Updates

Apply security patches provided by Sophos to address the Local Privilege Escalation vulnerability in SafeGuard products.