CVE-2026-17539: RTU500 has a vulnerability, where high-load scenarios, such as sending GI requests at short intervals, may cause a NULL pointer dereference in the last entry…

PriorityP429medium5.9CVSS 3.1

AVNACHPRNUINSUCNINAH

EPSS

0.35%

28.8th percentile

RTU500 has a vulnerability, where high-load scenarios, such as sending GI requests at short intervals, may cause a NULL pointer dereference in the last entry of the enhanced message queue. This can cause a BCI_IEC104 fatal write error, resulting in connection interruption and restart, and ultimately a denial of service for bidirectional IEC 60870-5-104 communication.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
hitachi_energy	rtu500_series_cmu_firmware	12.7.1 – 12.7.7	—
hitachi_energy	rtu500_series_cmu_firmware	13.5.1 – 13.5.4	—
hitachi_energy	rtu500_series_cmu_firmware	13.6.1 – 13.6.3	—
hitachi_energy	rtu500_series_cmu_firmware	13.7.1 – 13.7.8	—
hitachi_energy	rtu500_series_cmu_firmware	13.8.1 – 13.8.2	—

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