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 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.

  • Published Sep 3, 2026
  • CVSS 5.9 medium
  • 0.3% chance of exploitation in the next 30 days (EPSS)

Affected software

CVE-2026-17539 at the National Vulnerability Database