CVE-2020-25241 Explained : Impact and Mitigation

A vulnerability has been identified in SIMATIC MV400 family (All Versions < V7.0.6) that could allow an attacker to terminate arbitrary TCP sessions by exploiting a flaw in the TCP stack's sequence number validation.

Understanding CVE-2020-25241

This CVE affects Siemens' SIMATIC MV400 family devices.

What is CVE-2020-25241?

The vulnerability in SIMATIC MV400 family devices allows attackers to terminate TCP sessions by exploiting a flaw in sequence number validation.

The Impact of CVE-2020-25241

The vulnerability could be exploited by malicious actors to disrupt TCP sessions, leading to potential service interruptions and security breaches.

Technical Details of CVE-2020-25241

This section provides technical details about the vulnerability.

Vulnerability Description

The TCP stack in affected SIMATIC MV400 family devices fails to properly validate sequence numbers in incoming TCP RST packets, enabling attackers to terminate TCP sessions.

Affected Systems and Versions

Product: SIMATIC MV400 family
Vendor: Siemens
Versions Affected: All Versions < V7.0.6

Exploitation Mechanism

Attackers can exploit the vulnerability by sending malicious TCP RST packets with incorrect sequence numbers, causing the targeted device to terminate TCP sessions.

Mitigation and Prevention

Protect your systems from CVE-2020-25241 with the following steps:

Immediate Steps to Take

Apply vendor-supplied patches or updates promptly.
Implement network segmentation to limit the impact of potential attacks.
Monitor network traffic for any suspicious activity.

Long-Term Security Practices

Regularly update and patch all software and firmware.
Conduct security assessments and penetration testing to identify vulnerabilities.
Educate users and IT staff on best security practices.
Implement intrusion detection and prevention systems.

Patching and Updates

Ensure that all affected SIMATIC MV400 family devices are updated to version V7.0.6 or higher to mitigate the vulnerability.