Vulnerability · Published Jul 30, 2026 · Assigned by icscert
CVE-2026-66369MZ Automation libiec61850 Out-of-bounds Read
Medium 6.5
In plain English
A medium-severity out-of-bounds read in libiec61850 from MZ Automation GmbH. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| MZ Automation GmbH | libiec61850 | 0 – before 1.6.2 |
Weakness: CWE-125 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H