CVE-2018-6853 : Security Advisory and Response

Sophos SafeGuard Enterprise, SafeGuard Easy, and SafeGuard LAN Crypt versions prior to specified versions are vulnerable to a Local Privilege Escalation vulnerability through IOCTL 0x80206024. This flaw allows an attacker to execute code in the context of a SYSTEM process.

Understanding CVE-2018-6853

This CVE details a vulnerability in Sophos SafeGuard products that can lead to Local Privilege Escalation.

What is CVE-2018-6853?

The vulnerability in Sophos SafeGuard products allows attackers to manipulate an input buffer to control the flow of execution, leading to privilege escalation.

The Impact of CVE-2018-6853

Exploiting this vulnerability can result in executing code within a privileged process running as SYSTEM, potentially leading to unauthorized access and control of the system.

Technical Details of CVE-2018-6853

This section provides technical insights into the vulnerability.

Vulnerability Description

By exploiting IOCTL 0x80206024, attackers can overwrite pointers to security descriptors in privileged processes, enabling code execution as SYSTEM.

Affected Systems and Versions

Sophos SafeGuard Enterprise versions before 8.00.5
SafeGuard Easy versions before 7.00.3
SafeGuard LAN Crypt versions before 3.95.2

Exploitation Mechanism

Crafting an input buffer to control execution flow
Writing global variables to user-controlled addresses
Zeroing out security descriptor pointers or modifying them to run code as SYSTEM

Mitigation and Prevention

Protect systems from CVE-2018-6853 with the following measures.

Immediate Steps to Take

Update Sophos SafeGuard products to the recommended versions
Monitor system activity for any signs of exploitation

Long-Term Security Practices

Implement the principle of least privilege to restrict access
Regularly audit and update security configurations

Patching and Updates

Apply patches and updates provided by Sophos to address the vulnerability