# CVE-2026-68907: libIEC61850 buffer over-read in dataset access handler

Source: https://junglewise.ai/threats/cve-2026-68907-libiec61850-is-an-open-source-implementation-of-iec-61850-client  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-16. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-68907 · Severity: info · Published 2026-10-16

libIEC61850 is an open-source library implementing industrial power system protocols for control and protection systems. A remote attacker can crash servers running the MMS protocol with dynamic dataset services by sending a specially crafted defineNamedVariableList request, causing a denial-of-service that may disrupt critical grid operations. The vulnerability requires the server to have a dataset access handler installed but affects all exposed instances.

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

## Quick answers

**Is CVE-2026-68907 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-68907 being exploited in the wild.

**How severe is CVE-2026-68907?** Informational severity, published 16 October 2026.

**Which products and versions are affected?** MZ Automation libIEC61850 before 1.6.2.

**Is there a fix for CVE-2026-68907?** 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-2026-68907 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-68907?** 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

An off-by-one argument swap in checkDataSetAccess causes StringUtils_copyStringToBuffer to read from uninitialized stack memory (dataSetRef[130]) as a source string, then copies the over-read bytes into the caller's listName buffer. The vulnerability is triggered via remote MMS defineNamedVariableList requests on association or VMD-specific datasets; no authentication is required. While stack corruption is possible, the primary confirmed impact is denial of service through server crash.

## Affected products

- mz-automation libIEC61850 before 1.6.2

## Timeline

- 2026-10-16: disclosed

## References

- [https://github.com/mz-automation/libiec61850/commit/062062daf4cb50c7aa76e01d6fb4d58fc9278a7d](https://github.com/mz-automation/libiec61850/commit/062062daf4cb50c7aa76e01d6fb4d58fc9278a7d)
- [https://github.com/mz-automation/libiec61850/releases/tag/v1.6.2](https://github.com/mz-automation/libiec61850/releases/tag/v1.6.2)

## 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 infinite loop in ACSE parseUserInformation](https://junglewise.ai/threats/cve-2026-68906-libiec61850-is-an-open-source-implementation-of-iec-61850-client)
- [libIEC61850 MMS ObtainFile double-free denial of service](https://junglewise.ai/threats/cve-2026-57446-libiec61850-is-an-open-source-implementation-of-iec-61850-client)
- [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)
- [libIEC61850 MMS file service information disclosure](https://junglewise.ai/threats/cve-2026-48503-libiec61850-is-an-open-source-implementation-of-iec-61850-client)