CVE-2021-23842 : Vulnerability Insights and Analysis

This CVE-2021-23842 advisory was published by Bosch on January 19, 2022, highlighting a significant vulnerability. The vulnerability stems from the use of a hard-coded cryptographic key in the communication protocol between the AMC2 device and the host system.

Understanding CVE-2021-23842

CVE-2021-23842, titled 'Use of Hard-coded Cryptographic Key,' exposes a flaw in the AMC2 system's encryption process, allowing attackers to potentially decrypt network traffic and manipulate device configurations.

What is CVE-2021-23842?

The vulnerability in CVE-2021-23842 arises from the reliance on a fixed cryptographic key within the AMC2 device, enabling unauthorized access to decrypted network traffic and sensitive device data.

The Impact of CVE-2021-23842

With a CVSS score of 5.7, this vulnerability poses a medium risk, primarily affecting confidentiality. An attacker with access to the local network could potentially intercept and modify network traffic, compromising data integrity.

Technical Details of CVE-2021-23842

The vulnerability description, affected systems, and exploitation mechanism are crucial aspects to consider for mitigation strategies.

Vulnerability Description

The AMC2 employs the Blowfish algorithm for symmetric encryption and utilizes a hardcoded cryptographic key. This oversight allows malicious actors to intercept and decrypt network traffic, exposing sensitive information.

Affected Systems and Versions

The vulnerability impacts various Bosch products, including AMS, APE, BIS (up to version 4.9.1), and all versions of AMC2. Systems with versions lower than 4.0, 3.8.x, and 4.9.1 are particularly susceptible.

Exploitation Mechanism

Attackers can exploit this vulnerability by accessing the local network or the same subnet, intercepting network traffic, and decrypting confidential data.

Mitigation and Prevention

Understanding the immediate steps to take and ensuring long-term security practices are essential in addressing and preventing CVE-2021-23842.

Immediate Steps to Take

It is recommended to restrict network access to the AMC2 device, update to the patched firmware, and monitor network traffic for any suspicious activity.

Long-Term Security Practices

Implement a robust key management system, conduct regular security audits, and prioritize network segmentation to isolate critical systems.

Patching and Updates

Bosch has released patches and updates to address the vulnerability. Ensure timely installation of the latest firmware versions to mitigate the risk of exploitation.