CVE-2026-66369 PUBLISHED

MZ Automation libiec61850 Out-of-bounds Read

Assigner: icscert
Reserved: 27.07.2026 Published: 30.07.2026 Updated: 30.07.2026

The GOOSE parser contains an off-by-one boundary-handling flaw that can be triggered by a single unauthenticated Layer-2 multicast frame on the process bus. When specific GOOSE message fields are processed, the parser advances its internal buffer position incorrectly, resulting in a heap out-of-bounds read. On affected platforms, this condition reliably terminates the subscriber process and causes a denial-of-service.

Metrics

CVSS Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 7.1

Product Status

Vendor MZ Automation GmbH
Product libiec61850
Versions Default: unaffected
  • affected from 0 to 1.6.2 (excl.)
  • Version 1.6.2 is unaffected

Solutions

MZ Automation GmbH recommends that users update to version 1.6.2.

Credits

  • Arun Babu of Central Power Research Institute reported this vulnerability to CISA. finder

References

Problem Types

  • CWE-125 CWE