Moxa’s Ethernet switch EDS-508A Series, running firmware version 3.11 and earlier, is vulnerable to an authentication bypass because of flaws in its authorization mechanism. Although both client-side and back-end server verification are involved in the process, attackers can exploit weaknesses in its implementation. These vulnerabilities may enable brute-force attacks to guess valid credentials or MD5 collision attacks to forge authentication hashes, potentially compromising the security of the device.

The identified vulnerability types and potential impacts are listed below:

Vulnerability Scoring Details 

Affected Products:

The affected products and firmware versions are listed below.

Solutions:

Moxa has developed appropriate solutions to address vulnerability. The solutions for the affected products are listed below.

Mitigations:

• Minimize network exposure to ensure the device is not accessible from the Internet.
• Limit SSH access to trusted IP addresses and networks using firewall rules or TCP wrappers.
• Implement IDS or Intrusion Prevention System (IPS) to detect and prevent exploitation attempts. These systems can provide an additional layer of defense by monitoring network traffic for signs of attacks.

Acknowledgement:

We would like to express our gratitude to Artem Turyshev from Rosatom Automated Control Systems Joint-Stock Company for reporting the vulnerability, collaborating with us to enhance the security of our products, and contributing to our efforts to deliver better service to our customers.

Revision History: