CVE-2021-27196: Specially Crafted IEC 61850 Protocol Sequence Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-14 · updated 2026-06-17
Weakness: CWE-20

Description

Improper Input Validation vulnerability in Hitachi ABB Power Grids Relion 670 Series, Relion 670/650 Series, Relion 670/650/SAM600-IO, Relion 650, REB500, RTU500 Series, FOX615 (TEGO1), MSM, GMS600, PWC600 allows an attacker with access to the IEC 61850 network with knowledge of how to reproduce the attack, as well as the IP addresses of the different IEC 61850 access points (of IEDs/products), to force the device to reboot, which renders the device inoperable for approximately 60 seconds. This vulnerability affects only products with IEC 61850 interfaces. This issue affects: Hitachi ABB Power Grids Relion 670 Series 1.1; 1.2.3 versions prior to 1.2.3.20; 2.0 versions prior to 2.0.0.13; 2.1; 2.2.2 versions prior to 2.2.2.3; 2.2.3 versions prior to 2.2.3.2. Hitachi ABB Power Grids Relion 670/650 Series 2.2.0 versions prior to 2.2.0.13. Hitachi ABB Power Grids Relion 670/650/SAM600-IO 2.2.1 versions prior to 2.2.1.6. Hitachi ABB Power Grids Relion 650 1.1; 1.2; 1.3 versions prior to 1.3.0.7. Hitachi ABB Power Grids REB500 7.3; 7.4; 7.5; 7.6; 8.2; 8.3. Hitachi ABB Power Grids RTU500 Series 7.x version 7.x and prior versions; 8.x version 8.x and prior versions; 9.x version 9.x and prior versions; 10.x version 10.x and prior versions; 11.x version 11.x and prior versions; 12.x version 12.x and prior versions. Hitachi ABB Power Grids FOX615 (TEGO1) R1D02 version R1D02 and prior versions. Hitachi ABB Power Grids MSM 2.1.0 versions prior to 2.1.0. Hitachi ABB Power Grids GMS600 1.3.0 version 1.3.0 and prior versions. Hitachi ABB Power Grids PWC600 1.0 versions prior to 1.0.1.4; 1.1 versions prior to 1.1.0.1.

Affected products

Hitachienergy Fox615 Tego1 Firmware: before r2a16 — fixed in r2a16
Hitachienergy Gms600 Firmware: through 1.3.0
Hitachienergy Modular Switchgear Monitoring Firmware: before 2.1.0 — fixed in 2.1.0
Hitachienergy Pwc600 Firmware: from 1.0 before 1.0.1.4; from 1.1 before 1.1.0.1 — fixed in 1.0.1.4, 1.1.0.1
Hitachi Energy Relion REB500: from 7.3 before 7.60.19; from 8.2 before 8.2.0.5; from 8.3 through 8.3.1.0 — fixed in 7.60.19, 8.2.0.5
Hitachienergy Relion 650 Firmware: from 1.3 before 1.3.0.7; from 2.2.0 before 2.2.0.13; from 2.2.1 before 2.2.1.6; 1.1, 1.2, 2.1 — fixed in 1.3.0.7, 2.2.0.13, 2.2.1.6
Relion 670 Series: from 1.2.3 before 1.2.3.20; from 2.0 before 2.0.0.13; from 2.2.0 before 2.2.0.13; from 2.2.1 before 2.2.1.6; from 2.2.2 before 2.2.2.3; from 2.2.3 before 2.2.3.2 — fixed in 1.2.3.20, 2.0.0.13, 2.2.0.13, 2.2.1.6, 2.2.2.3, 2.2.3.2
Hitachienergy Relion Sam600-Io Firmware: from 2.2.1 before 2.2.1.6 — fixed in 2.2.1.6
Hitachi Energy RTU500 series CMU firmware: 7.0, 8.0, 9.0, 10.0, 11.0, 12.0

How to fix

Upgrade to a fixed version: Hitachienergy Fox615 Tego1 Firmware r2a16; Hitachienergy Modular Switchgear Monitoring Firmware 2.1.0; Hitachienergy Pwc600 Firmware 1.0.1.4, 1.1.0.1; Hitachi Energy Relion REB500 7.60.19, 8.2.0.5; Hitachienergy Relion 650 Firmware 1.3.0.7, 2.2.0.13, 2.2.1.6; Relion 670 Series 1.2.3.20, 2.0.0.13, 2.2.0.13, 2.2.1.6; Hitachienergy Relion Sam600-Io Firmware 2.2.1.6. Check the vendor advisory for mitigations.

References

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