CVE-2026-8066

CRITICAL CVSS 3.1: 9.1 EPSS 0.74%
Updated Sep 30, 2026
Hitachi Energy
Parameter Value
CVSS 9.1 (CRITICAL)
Type CWE-23 (Relative Path Traversal)
Vendor Hitachi Energy
Public PoC No

A directory traversal vulnerability in the file upload functionality of Hitachi Energy RTU500 end-of-life versions allows an unauthenticated attacker to write or overwrite arbitrary files on the device file system. Depending on the files affected, successful exploitation could result in unauthorized modification of device data or disruption of the device’s intended operation.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
None
No data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v3.1

Vulnerable Products

hitachi energy:rtu500 series cmu firmware