CVE-2020-22552 : Vulnerability Insights and Analysis

Snap7 server component in version 1.4.1 crashes when receiving a crafted packet with specific parameters.

Understanding CVE-2020-22552

The vulnerability in the Snap7 server component allows attackers to crash the server by sending a malicious packet.

What is CVE-2020-22552?

The Snap7 server component in version 1.4.1 crashes when an attacker sends a crafted packet with specific parameters.

The Impact of CVE-2020-22552

Successful exploitation can lead to a denial of service (DoS) condition by crashing the Snap7 server.

Technical Details of CVE-2020-22552

The technical aspects of the vulnerability in the Snap7 server component.

Vulnerability Description

The Snap7 server crashes when receiving a crafted packet with the COTP protocol and specific flags set.

Affected Systems and Versions

Snap7 server version 1.4.1 is affected.

Exploitation Mechanism

Attacker sends a crafted packet with the last-data-unit flag set to No and S7 writes a var function, causing the server to crash.

Mitigation and Prevention

Steps to mitigate and prevent the exploitation of CVE-2020-22552.

Immediate Steps to Take

Update Snap7 server to a patched version if available.
Implement network segmentation to limit exposure.
Monitor network traffic for any suspicious activity.

Long-Term Security Practices

Regularly update software and firmware to the latest versions.
Conduct security assessments and penetration testing to identify vulnerabilities.

Patching and Updates

Apply patches provided by the vendor to fix the vulnerability.