# CVE-2026-50103: MZ Automation libIEC61850 NULL pointer dereference in GOOSE parser

Source: https://junglewise.ai/threats/cve-2026-50103-mz-automation-libiec61850-null-pointer-dereference-in-goose  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-23. Updated: 2026-07-23  
License: CC BY 4.0 with a link back

CVE-2026-50103 · Severity: medium · CVSS 6.5 · Published 2026-07-23

A vulnerability exists in a specialized software library used by industrial control systems in the energy and manufacturing sectors to communicate over power grid protocols. An attacker on the same local network can send a specially crafted message to crash applications that rely on this library for monitoring or control. This could lead to a loss of visibility or control over critical infrastructure equipment, potentially disrupting operations.

Technologies: [MZ Automation libIEC61850](https://junglewise.ai/threats/technologies/libiec61850). Vendors: [MZ Automation](https://junglewise.ai/threats/vendors/mz-automation).

## Quick answers

**Is CVE-2026-50103 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-50103 being exploited in the wild.

**How severe is CVE-2026-50103?** Medium severity, with a CVSS score of 6.5, published 23 July 2026.

**Which products and versions are affected?** MZ Automation libIEC61850 >=v1.0.0, <=v1.6.1.

**Is there a fix for CVE-2026-50103?** 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-2026-50103 attacked?** It is attacked from the adjacent network, in a software library.

**Am I affected by CVE-2026-50103?** Check whether you run MZ Automation libIEC61850 at an affected version. 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

The vulnerability is a NULL pointer dereference (CWE-228/CWE-476) within the shared parser for Layer 2 GOOSE and Routable GOOSE (R-GOOSE) protocols in libIEC61850. The flaw is triggered when the parser encounters a malformed Type-Length-Value (TLV) structure in a crafted GOOSE frame. An unauthenticated attacker located on the same network segment (adjacent) can exploit this to cause a denial-of-service (DoS) condition by crashing the subscribing application. The issue affects versions 1.0.0 through 1.6.1; users are advised to update to the latest build from the vendor's repository.

## Affected products

- MZ Automation libIEC61850 >=v1.0.0, <=v1.6.1

## Timeline

- 2026-07-23: disclosed
- 2026-07-23: advisory

## References

- [https://www.cisa.gov/news-events/ics-advisories/icsa-26-204-06](https://www.cisa.gov/news-events/ics-advisories/icsa-26-204-06)

## Related threats

- [libIEC61850 invalid free in MMS report serialization](https://junglewise.ai/threats/cve-2026-68908-libiec61850-is-an-open-source-implementation-of-iec-61850-client)
- [libIEC61850 buffer over-read in dataset access handler](https://junglewise.ai/threats/cve-2026-68907-libiec61850-is-an-open-source-implementation-of-iec-61850-client)
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- [libIEC61850 NULL pointer dereference in MMS read service](https://junglewise.ai/threats/cve-2026-48741-libiec61850-is-an-open-source-implementation-of-iec-61850-client)