CVE-2021-35534Network attack vector

Firmware modification via unrestricted database table access

Published Nov 18, 2021 · Updated Sep 16, 2024

Improper privilege handling in affected Hitachi Energy industrial devices allows remote authenticated users to alter firmware and data. The internal database access mechanism fails to restrict authenticated accounts from accessing tables beyond their assigned security controls. Valid credentials are required, and successful access permits unauthorized changes that can permanently disable the device.

CVSS severity7.2
High
EPSS probability1.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper privilege handling in affected Hitachi Energy industrial devices allows remote authenticated users to alter firmware and data. The internal database access mechanism fails to restrict authenticated accounts from accessing tables beyond their assigned security controls. Valid credentials are required, and successful access permits unauthorized changes that can permanently disable the device.

The record

CVE
CVE-2021-35534
Published
Nov 18, 2021
Updated
Sep 16, 2024
Vendor
Hitachi Energy
Product
Relion 650 series
Classifications
CWE-274, CWE-269, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0 all revisions
  2. Affected versionversion=1.1 all revisions
  3. Affected versionversion=1.2 all revisions
  4. Affected versionversion=1.3 <1.3.0.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Hitachi Energy · Relion 650 seriesversion=1.0 all revisions; version=1.1 all revisions; version=1.2 all revisions; version=1.3 <1.3.0.8
Hitachi Energy · GMS600version=1.2.0; version=1.3.0; version=1.3.1.0 1.3.0.1
Hitachi Energy · Switchsync PWC600version=1.0.1 <=1.0.1.4; version=1.1.0 <=1.1.0.1
Hitachi Energy · Relion 670 seriesversion=2.0 all revisions; version=2.2.2 all revisions; version=2.2.3 <2.2.3.5

Published CVSS scores

9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C
7.2Hitachi EnergyCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-274Improper Handling of Insufficient Privileges
CWE-269Improper Privilege Management
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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