CVE-2022-40267 : Vulnerability Insights and Analysis

This article delves into the authentication bypass vulnerability in the Web Server Function on the Mitsubishi Electric Corporation MELSEC Series devices.

Understanding CVE-2022-40267

CVE-2022-40267 highlights a Predictable Seed in Pseudo-Random Number Generator (PRNG) vulnerability affecting various Mitsubishi Electric Corporation MELSEC iQ-F Series and iQ-R Series devices.

What is CVE-2022-40267?

The CVE-2022-40267 vulnerability exposes Mitsubishi Electric Corporation MELSEC devices to a remote unauthenticated attacker who can potentially access the Web server function by guessing the random numbers used for authentication.

The Impact of CVE-2022-40267

This vulnerability poses a medium severity risk with a CVSS base score of 5.9. It has a medium base severity due to high integrity impact and high attack complexity. The confidentiality impact is none, and there is no availability impact.

Technical Details of CVE-2022-40267

CVE-2022-40267 affects a range of Mitsubishi Electric Corporation MELSEC devices including the iQ-F Series, iQ-R Series, FX5U-xMy/z series, FX5UC-xMy/z series, FX5UJ-xMy/z series, and FX5S-xMy/z series. The versions affected vary, such as serial number 17X**** or later and versions 1.280 and prior.

Vulnerability Description

The vulnerability arises from a Predictable Seed in Pseudo-Random Number Generator (PRNG) issue, allowing attackers to guess the random numbers used for authentication.

Affected Systems and Versions

Affected systems include numerous models from the MELSEC iQ-F Series, MELSEC iQ-R Series, as well as specific versions of FX5U and FX5UC series devices.

Exploitation Mechanism

Remote unauthenticated attackers exploit this vulnerability by leveraging guessed random numbers to access the Web server function on these devices.

Mitigation and Prevention

To address CVE-2022-40267, immediate steps must be taken to secure the affected Mitsubishi Electric Corporation devices.

Immediate Steps to Take

Apply patches and updates provided by Mitsubishi Electric Corporation promptly.
Implement network security measures to mitigate unauthorized access.

Long-Term Security Practices

Regularly update firmware and software on MELSEC devices.
Conduct security assessments and penetration testing to identify and address vulnerabilities.

Patching and Updates

Stay informed about security advisories and patches released by Mitsubishi Electric Corporation to safeguard against authentication bypass vulnerabilities.