CVE-2018-6851 Explained : Impact and Mitigation

Sophos SafeGuard Enterprise, SafeGuard Easy, and SafeGuard LAN Crypt versions prior to specified versions have a vulnerability allowing local privilege escalation via IOCTL 0x80206040.

Understanding CVE-2018-6851

This CVE involves a vulnerability in Sophos SafeGuard products that can be exploited for local privilege escalation.

What is CVE-2018-6851?

The vulnerability in Sophos SafeGuard products allows an attacker to manipulate an input buffer to control the execution path, leading to writing a constant DWORD 0 to a user-controlled address. This manipulation can enable zeroing-out the pointer to the security descriptor or modifying the security descriptor to execute code within a process running as SYSTEM.

The Impact of CVE-2018-6851

Exploiting this vulnerability can result in unauthorized users gaining elevated privileges on affected systems, potentially leading to further compromise and unauthorized access.

Technical Details of CVE-2018-6851

This section provides more technical insights into the vulnerability.

Vulnerability Description

The vulnerability in Sophos SafeGuard products allows for local privilege escalation by manipulating an input buffer to control the execution path, enabling unauthorized code execution.

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

By crafting an input buffer, attackers can control the execution path to write a constant DWORD 0 to a user-controlled address, facilitating privilege escalation and unauthorized code execution.

Mitigation and Prevention

Protecting systems from CVE-2018-6851 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update Sophos SafeGuard products to the latest patched versions to mitigate the vulnerability.
Monitor system logs for any suspicious activities indicating exploitation attempts.

Long-Term Security Practices

Implement the principle of least privilege to restrict user access and limit potential damage from privilege escalation attacks.
Regularly conduct security assessments and penetration testing to identify and address vulnerabilities proactively.

Patching and Updates

Stay informed about security updates and patches released by Sophos for SafeGuard products.
Apply patches promptly to ensure systems are protected against known vulnerabilities.