CVE-2020-12517 : Vulnerability Insights and Analysis

Phoenix Contact PLCnext Control Devices versions before 2021.0 LTS have a vulnerability that allows an authenticated low privileged user to embed malicious Javascript code, potentially gaining admin rights when the admin user visits the vulnerable website.

Understanding CVE-2020-12517

This CVE involves a local privilege escalation issue on Phoenix Contact PLCnext Control Devices.

What is CVE-2020-12517?

This CVE refers to a security flaw in Phoenix Contact PLCnext Control Devices versions prior to 2021.0 LTS. It enables a low privileged user to inject malicious Javascript code, leading to potential admin rights escalation when the admin user accesses the compromised website.

The Impact of CVE-2020-12517

The vulnerability has a CVSS base score of 8.8 (High severity) with significant impacts on confidentiality, integrity, and availability. An attacker could exploit this flaw to execute unauthorized actions on the affected system.

Technical Details of CVE-2020-12517

This section provides more in-depth technical insights into the CVE.

Vulnerability Description

The vulnerability allows an authenticated low privileged user to insert malicious Javascript code, potentially escalating privileges to gain admin rights.

Affected Systems and Versions

Products affected: AXC F 1152, AXC F 2152, AXC F 3152, RFC 4072S, AXC F 2152 Starterkit, PLCnext Technology Starterkit
Vendor: Phoenix Contact
Vulnerable versions: Versions before 2021.0 LTS

Exploitation Mechanism

An attacker with low privileges can exploit the vulnerability by embedding malicious Javascript code, which triggers when the admin user visits the compromised website, leading to local privilege escalation.

Mitigation and Prevention

Protecting systems from CVE-2020-12517 requires immediate actions and long-term security practices.

Immediate Steps to Take

Upgrade to Firmware 2021.0 LTS or higher as recommended by Phoenix Contact.
Operate network-capable devices in closed networks or behind a suitable firewall.

Long-Term Security Practices

Regularly update firmware and software to patch known vulnerabilities.
Implement network segmentation and access controls to limit the impact of potential breaches.

Patching and Updates

Ensure all devices are updated to the latest firmware version (2021.0 LTS or higher) to mitigate the vulnerability.