Vulnerability in Hitachi Energy Rtu500 Series Cmu Firmware
CVE-2026-1773
IEC 60870-5-104 used in RTU500: Potential Denial of Service impact on reception of invalid U-format frame. Product is only affected if IEC 60870-5-104 bi-directional functionality is configured. Enabling secure communication following IEC 62351-3 does not remediate the vulnerability but mitigates the risk of exploitation.
EPSS: 0.004 (33.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Hitachi Energy Rtu500 Series Cmu Firmware — versions 12.7.1, 13.5.1, 13.6.1
- Hitachienergy Rtu520
- Hitachienergy Rtu520_firmware — versions 13.8.1
- Hitachienergy Rtu530
- Hitachienergy Rtu530_firmware — versions 13.8.1
- Hitachienergy Rtu540
- Hitachienergy Rtu540_firmware — versions 13.8.1
- Hitachienergy Rtu560
- Hitachienergy Rtu560_firmware — versions 13.8.1
Weakness classification (CWE)
References
- cybersecurity@hitachienergy.com (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-1773?
- CVE-2026-1773 is a high-severity vulnerability in Hitachi Energy Rtu500 Series Cmu Firmware, classified under Incomplete List of Disallowed Inputs. CVSS score: 7.5/10. Published 2026-02-24.
- How severe is CVE-2026-1773?
- High severity. CVSS v3 base score is 7.5 out of 10.