Out-of-bounds Read in Mz Automation Gmbh Libiec61850

CVE-2026-66364

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.

Vulnerability class: Buffer Overflow

EPSS: 0.002 (7.1th percentile) — read the EPSS interpretation.