Hitachi RTU500 and REB500 Firmware Flaws Require Updates

An unprivileged user can read user-management information. Malformed IEC 60870-5-104 U-frames can disrupt RTU operation, and authenticated REB500 roles can access or alter unauthorized directories; devices are deployed in the energy sector and other critical infrastructure.

Part of the PlainSec briefing for 2026-03-04

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