# CVE-2026-66360: MZ Automation libiec61850 out-of-bounds read in ISO Presentation layer

Source: https://junglewise.ai/threats/cve-2026-66360-mz-automation-libiec61850-out-of-bounds-read-in-iso-presentation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-30. Updated: 2026-07-30  
License: CC BY 4.0 with a link back

CVE-2026-66360 · Severity: high · CVSS 7.5 · Published 2026-07-30

A vulnerability exists in a specialized communication library used in energy and industrial automation systems. An attacker can send a specially crafted network request to a device using this library, causing the system to crash and become unavailable. This results in a denial-of-service condition that could disrupt critical infrastructure operations.

## Quick answers

**Is CVE-2026-66360 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-66360 being exploited in the wild.

**How severe is CVE-2026-66360?** High severity, with a CVSS score of 7.5, published 30 July 2026.

**Which products and versions are affected?** MZ Automation GmbH libiec61850 < 1.6.2.

**Is there a fix for CVE-2026-66360?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-66360 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-66360?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An out-of-bounds read vulnerability (CWE-125) exists in the ISO Presentation layer of libiec61850 due to a missing length check during normal mode negotiation. Specifically, the processing of encoded presentation data fails to validate attacker-controlled fields, where a zero-length value triggers a bounded heap over-read. This flaw can be exploited remotely via a crafted TCP port 102 connection attempt before an MMS session is even established. Successful exploitation causes the process to terminate, resulting in a denial-of-service (DoS) condition. The issue is resolved in version 1.6.2.

## Affected products

- MZ Automation GmbH libiec61850 < 1.6.2

## Timeline

- 2026-07-30: advisory: CISA ICSA-26-211-10 published
- 2026-07-30: disclosed: CVE-2026-66360 published in NVD

## References

- [https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-10.json](https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-10.json)
- [https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-10](https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-10)