Vulnerability · Published Sep 3, 2026 · Assigned by Hitachi Energy
CVE-2026-17539
Medium 5.9
In plain English
A medium-severity null pointer dereference in RTU500 series CMU firmware from Hitachi Energy. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 31% of all known vulnerabilities).
Official description
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 products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Hitachi Energy | RTU500 series CMU firmware | 12.7.1 – through 12.7.713.5.1 – through 13.5.413.6.1 – through 13.6.313.7.1 – through 13.7.813.8.1 – through 13.8.2 |
Weakness: CWE-476 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H