CVE-2026-66720 (GCVE-0-2026-66720)
Vulnerability from cvelistv5 – Published: 2026-07-30 22:46 – Updated: 2026-07-31 15:58
VLAI
EPSS
VEX
Title
MZ Automation libiec61850 Out-of-bounds Read
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-31 15:58 UTC
CWE
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| MZ Automation GmbH | libiec61850 |
Affected:
0 , < 1.6.2
(custom)
Unaffected: 1.6.2 |
guessed |
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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