CVE-2021-27196 Explained : Impact and Mitigation

A vulnerability in Hitachi ABB Power Grids products allows an attacker to force the device to reboot, rendering it inoperable for a short duration.

Understanding CVE-2021-27196

This CVE describes an Improper Input Validation vulnerability affecting Hitachi ABB Power Grids products with IEC 61850 interfaces.

What is CVE-2021-27196?

The vulnerability allows an attacker on the IEC 61850 network to force a device reboot, causing it to be inoperable for about 60 seconds. Only products with IEC 61850 interfaces are affected.

The Impact of CVE-2021-27196

The vulnerability has a CVSS base score of 7.5, indicating a high severity issue with a significant impact on system availability.

Technical Details of CVE-2021-27196

The vulnerability affects various Hitachi ABB Power Grids products including Relion 670 Series, Relion 650 Series, REB500, RTU500 Series, FOX615, MSM, GMS600, and PWC600.

Vulnerability Description

The vulnerability arises due to improper input validation, allowing attackers to trigger a device reboot through the IEC 61850 network.

Affected Systems and Versions

Multiple versions of the affected product lines are susceptible to this vulnerability, including specific versions of Relion 670 Series, Relion 650 Series, and others.

Exploitation Mechanism

An attacker with knowledge of the IEC 61850 network can initiate a sequence that forces the affected device to reboot.

Mitigation and Prevention

To address CVE-2021-27196, immediate action and long-term security practices are essential.

Immediate Steps to Take

Users are advised to refer to the cybersecurity advisories provided by Hitachi ABB Power Grids.

Long-Term Security Practices

Regular security updates, network segmentation, and access control measures can help prevent attacks exploiting this vulnerability.

Patching and Updates

It is crucial to apply patches and updates from Hitachi ABB Power Grids to mitigate the risk of exploitation.