CVE-2026-66369

MediumCVSS 6.5

Published: 30/07/2026(UTC)Updated: 03/09/2026(UTC)Translated: 31/07/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.18%

7th percentile - higher than 7% of all known CVEs

Summary

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. This reliably terminates the subscriber process and causes a denial-of-service.

Risk Assessment

An attacker can remotely crash the GOOSE subscriber process, disrupting communication in power automation systems and potentially causing power supply interruptions.

Recommendation

Install the update provided by the power automation system vendor that fixes the off-by-one error in the GOOSE parser.

Other vulnerabilities in GOOSE parser

CVE-2026-50103Medium
A NULL pointer dereference in the L2 GOOSE and R-GOOSE shared parser may allow a network-adjacent attacker to crash a subscribing application by sending a crafted GOOSE frame with a malformed TLV value.

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS