CVE-2021-35535

What it is

Insecure Boot Image vulnerability in Hitachi Energy Relion Relion 670/650/SAM600-IO series allows an attacker who manages to get access to the front network port and to cause a reboot sequences of the device may exploit the vulnerability, where there is a tiny time gap during the booting process where an older version of VxWorks is loaded prior to application firmware booting, could exploit the vulnerability in the older version of VxWorks and cause a denial-of-service on the product. This issue affects: Hitachi Energy Relion 670 Series 2.2.2 all revisions; 2.2.3 versions prior to 2.2.3.3. Hitachi Energy Relion 670/650 Series 2.2.0 all revisions; 2.2.4 all revisions. Hitachi Energy Relion 670/650/SAM600-IO 2.2.1 all revisions.

At a glance

Exploitability

Can be exploited locally on the machine without logging in. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.7% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2021-11-18 16:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 03:57 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.7% in the next 30 days (EPSS).
• Severity: 8.1 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2021-11-18 16:15 UTC

Last modified

2026-06-17 03:57 UTC

Exploit probability

0.7% · EPSS, next 30 days

Weakness

CWE-1188

Record status

Modified

Affected

• Hitachienergy Relion 670 Firmware ≤ 2.2.3.3
• Hitachienergy Relion 670 Firmware 2.2.0
• Hitachienergy Relion 670 Firmware 2.2.1
• Hitachienergy Relion 670 Firmware 2.2.2
• Hitachienergy Relion 670 Firmware 2.2.4
• Hitachienergy Relion 650 Firmware 2.2.0
• Hitachienergy Relion 650 Firmware 2.2.1
• Hitachienergy Relion 650 Firmware 2.2.4

Attack profile CVSS 3.1 · 8.1

Attack vector

Local

Complexity

High

Privileges needed

None

User interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2021-35535.md and follow it. Check whether this project is affected by CVE-2021-35535. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

Copy as ticket · More options · Status badge