PT-2026-66634 · Mz Automation Gmbh · Libiec61850

Arun Babu · CVE-2026-66720 · Published 2026-07-30 · Updated 2026-07-30

NVD

CVSS v3.1

6.5

Medium

Base vector

AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

The GOOSE subscriber component improperly validates the UTC timestamp field in unauthenticated IEC 61850 GOOSE (EtherType 0x88B8) Layer-2 multicast messages. A specially crafted GOOSE frame containing an undersized timestamp field can trigger a heap out-of-bounds read during message processing, causing the process to crash and resulting in a denial-of-service condition.

Fix

Out of bounds Read

Weakness Enumeration

CWE-125

Related Identifiers

CVE-2026-66720

Affected Products

Libiec61850

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-66720 · Security Note
• https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-10.json · Note
• https://cisa.gov/news-events/ics-advisories/icsa-26-211-10 · Note