CVE-2023-0811 Explained : Impact and Mitigation

This CVE record pertains to a vulnerability identified in Omron CJ1M units version 4.0 and earlier. The vulnerability could allow an attacker to manipulate the UM (User Memory) password, potentially leading to the bypassing of UM protections or setting a non-ASCII password, which could hinder legitimate user access and control.

Understanding CVE-2023-0811

This section delves into the specifics of CVE-2023-0811, outlining its characteristics and potential impact.

What is CVE-2023-0811?

The CVE-2023-0811 vulnerability affects Omron CJ1M units with a version of 4.0 and below, exposing an improper access control issue in the memory region where the UM password is stored. By exploiting this vulnerability, an adversary could overwrite the password, potentially compromising system integrity and accessibility.

The Impact of CVE-2023-0811

The impact of CVE-2023-0811 is significant, as unauthorized manipulation of the UM password could result in disabling security protections, setting non-standard passwords, and obstructing the viewing and modification of user programs by legitimate users or engineers.

Technical Details of CVE-2023-0811

In this section, we will explore the technical aspects of CVE-2023-0811, including the vulnerability description, affected systems, and exploitation mechanism.

Vulnerability Description

Omron CJ1M units version 4.0 and earlier exhibit improper access controls in the UM password memory region, allowing attackers to overwrite the password and potentially compromise system security and accessibility.

Affected Systems and Versions

The vulnerability impacts Omron CJ1M units running version 4.0 and prior, leaving them susceptible to unauthorized password manipulation and security bypass.

Exploitation Mechanism

Attackers can exploit this vulnerability by issuing a PROGRAM AREA WRITE command to a specific memory region, enabling them to overwrite the UM password and undermine system protections.

Mitigation and Prevention

To address the CVE-2023-0811 vulnerability and enhance system security, users can implement a set of immediate steps and adopt long-term security practices.

Immediate Steps to Take

Enable the hardware switch to prohibit writing UM.
Set UM read protection password and choose the "Prohibit from overwriting to a protected program" option.
Apply security measures to prevent unauthorized access, such as enabling FINS write protection and selecting Protect by IP Address.

Long-Term Security Practices

Minimize connections of control systems to open networks.
Implement firewalls and isolate systems from the IT network.
Utilize VPN for remote access and enforce strong password policies.
Install physical access controls and employ multifactor authentication.
Conduct regular virus scans and data backups for protection.

Patching and Updates

Omron has released countermeasures to mitigate the vulnerability. If unable to apply the prescribed measures, users should adopt recommended security practices and refer to Omron's Security Advisory for comprehensive guidance on safeguarding systems.

By following these mitigation steps and best practices, organizations can enhance the security posture of their Omron CJ1M units and safeguard against potential exploitation of the CVE-2023-0811 vulnerability.