CVE-2020-24686 Explained : Impact and Mitigation

AC500 V2 webserver denial of service vulnerability

Understanding CVE-2020-24686

This CVE involves a denial of service vulnerability in the web visualization component of ABB's AC500 V2 products with onboard Ethernet.

What is CVE-2020-24686?

The vulnerability allows attackers to disrupt the web visualization component, causing genuine users to lose remote visibility of the PLC state. It triggers an error state when attempting to log in, leading to connection refusals to Automation Builder.

The Impact of CVE-2020-24686

Severity: High (CVSS Base Score: 7.5)
Attack Vector: Network
Availability Impact: High
No impact on Confidentiality or Integrity

Technical Details of CVE-2020-24686

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability results in the web visualization component of the PLC becoming unresponsive, affecting remote visibility and login attempts.

Affected Systems and Versions

Affected Product: AC500 V2 products with onboard Ethernet
Affected Version: All

Exploitation Mechanism

Attackers exploit the vulnerability to disrupt the web visualization component, leading to denial of service and connection refusals.

Mitigation and Prevention

Protecting systems from CVE-2020-24686 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply vendor-supplied patches or updates promptly.
Implement network segmentation to limit exposure.
Monitor network traffic for any signs of exploitation.

Long-Term Security Practices

Regularly update and patch all software and firmware.
Conduct security assessments and penetration testing.
Educate users on security best practices.

Patching and Updates

ABB may release patches or updates to address the vulnerability.