Is CVE-2026-48503 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-48503 being exploited in the wild.

How severe is CVE-2026-48503?

High severity, with a CVSS score of 7.5, published 16 October 2026.

Which products and versions are affected?

MZ Automation libIEC61850 prior to 1.6.2.

Is there a fix for CVE-2026-48503?

Yes: fixed in 1.6.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-48503 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-48503?

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.

CVE-2026-48503: libIEC61850 MMS file service information disclosure

CVE-2026-48503 · Severity: high · CVSS 7.5 · Published 2026-10-16

libIEC61850 is an open-source library implementing IEC 61850 protocols for power systems communication. An attacker can exploit an unvalidated file position parameter in the MMS file service to read beyond the requested file contents, exposing sensitive data from prior responses in the server's memory buffer to any remote client without authentication.

Technologies: MZ Automation libIEC61850. Vendors: MZ Automation.

Quick answers

Is CVE-2026-48503 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-48503 being exploited in the wild.
How severe is CVE-2026-48503?: High severity, with a CVSS score of 7.5, published 16 October 2026.
Which products and versions are affected?: MZ Automation libIEC61850 prior to 1.6.2.
Is there a fix for CVE-2026-48503?: Yes: fixed in 1.6.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-48503 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-48503?: 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.

How to fix

Fixed in: 1.6.2

Technical details

The MMS file service in libIEC61850 accepts an out-of-range initialPosition parameter in fileOpen without validation, stores it in the file-read state, and then performs unsigned arithmetic subtraction that wraps around when the position exceeds the file size. This causes fileRead to return a response larger than the actual file contents, leaking stale buffer data from prior responses to unauthenticated remote clients when the file service is enabled.

Affected products

MZ Automation libIEC61850 prior to 1.6.2

Timeline

2026-10-16: disclosed

References

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