CVE-2026-66360: Mz Automation GmbH LIBIEC61850

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

The ISO Presentation layer contains a flaw in the handling of specific parameters during normal mode negotiation. A missing length check in the processing of the encoded presentation data allows an attacker controlled field with a zero length value to trigger a bounded heap over read. This condition occurs before MMS session establishment, a crafted TCP/102 connection attempt can trigger the issue. The resulting over read causes the process to terminate, leading to a denial of service condition.

Affected products

• Mz Automation GmbH LIBIEC61850: before 1.6.2 (fixed in 1.6.2)

Published 2026-07-30. Last modified 2026-09-08.