MZ Automation libiec61850 Out-of-bounds Read
Summary
| CVE | CVE-2026-66364 |
|---|---|
| State | PUBLISHED |
| Assigner | icscert |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-30 23:16:53 UTC |
| Updated | 2026-07-31 16:17:10 UTC |
| Description | The GOOSE payload parser contains a boundary handling flaw that can be triggered by a single unauthenticated Layer 2 multicast frame on the process bus. When processing specific payload fields, an attacker controlled inner element length may exceed its enclosing length, causing the parser to over read by one byte. This out-of-bounds read reliably terminates the subscriber process, resulting in a denial-of-service condition. |
Risk And Classification
Primary CVSS: v4.0 7.1 HIGH from [email protected]
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.001750000 probability, percentile 0.071820000 (date 2026-08-01)
Problem Types: CWE-125 | CWE-125 CWE-125
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 7.1 | HIGH | 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/E:X/C... |
| 4.0 | CNA | CVSS | 7.1 | HIGH | 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 |
| 3.1 | [email protected] | Secondary | 6.5 | MEDIUM | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 6.5 | MEDIUM | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v4.0 Breakdown
Attack Vector
AdjacentAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
NoneConfidentiality
NoneIntegrity
NoneAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
AdjacentAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | MZ Automation GmbH | Libiec61850 | affected 1.6.2 custom | Not specified |
| CNA | MZ Automation GmbH | Libiec61850 | unaffected 1.6.2 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.cisa.gov/news-events/ics-advisories/icsa-26-211-10 | [email protected] | www.cisa.gov | |
| github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-21... | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Arun Babu of Central Power Research Institute reported this vulnerability to CISA. (en)
Additional Advisory Data
Solutions
CNA: MZ Automation GmbH recommends that users update to version 1.6.2.
There are currently no legacy QID mappings associated with this CVE.