# CVE-2026-61893: MZ Automation lib60870 out-of-bounds read in TestCommand_getFromBuffer

Source: https://junglewise.ai/threats/cve-2026-61893-mz-automation-lib60870-out-of-bounds-read-in-testcommand  
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-2026-61893 · Severity: medium · CVSS 6.5 · Published 2026-07-30

MZ Automation lib60870 is a software library used in industrial control systems to communicate using the IEC 60870-5-104 protocol, commonly found in energy and water utility networks. A vulnerability in how the library processes specific network messages could allow an attacker to crash the system or potentially read sensitive information from memory. This could lead to service disruptions in critical infrastructure operations if the affected devices become unresponsive.

Technologies: [MZ Automation Lib60870](https://junglewise.ai/threats/technologies/lib60870). Vendors: [MZ Automation](https://junglewise.ai/threats/vendors/mz-automation).

## Quick answers

**Is CVE-2026-61893 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-61893 being exploited in the wild.

**How severe is CVE-2026-61893?** Medium severity, with a CVSS score of 6.5, published 30 July 2026.

**Which products and versions are affected?** MZ Automation Lib60870 2.4.0.

**Is there a fix for CVE-2026-61893?** A patch was published on 2026-07-30: Version 2.4.1 released to address the issue Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-61893 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-61893?** Check whether you run MZ Automation Lib60870 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

An out-of-bounds read (CWE-125) exists in the TestCommand_getFromBuffer function within cs101_information_objects.c of lib60870-C v2.4.0. The vulnerability is caused by a structural omission where InformationObject_ParseObjectAddress is called without a message size parameter, preventing proper bounds checking. When a crafted IEC 60870-5-104 I-frame with TypeID 104 (C_TS_NA_1) and an inflated object count is processed, the parser reads one byte past the end of the heap-allocated message buffer. This can be triggered remotely over TCP port 2404 without authentication. The issue is addressed in version 2.4.1.

## Affected products

- MZ Automation lib60870 2.4.0

## Timeline

- 2026-07-15: advisory: Vendor advisory GHSA-g3w7-x5rx-83xm published
- 2026-07-30: disclosed: CISA Advisory ICSA-26-211-11 published
- 2026-07-30: patched: Version 2.4.1 released to address the issue

## References

- [https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-11.json](https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-11.json)
- [https://github.com/mz-automation/lib60870/security/advisories/GHSA-g3w7-x5rx-83xm](https://github.com/mz-automation/lib60870/security/advisories/GHSA-g3w7-x5rx-83xm)
- [https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-11](https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-11)

## Related threats

- [MZ Automation lib60870 out-of-bounds read in InformationObject_ParseObjectAddress](https://junglewise.ai/threats/cve-2026-63033-mz-automation-lib60870-out-of-bounds-read-in-informationobject)
- [MZ Automation lib60870 out-of-bounds read in parsing process](https://junglewise.ai/threats/cve-2026-16002-mz-automation-lib60870-out-of-bounds-read-in-parsing-process)
- [MZ Automation lib60870 heap buffer overflow in CS104 server](https://junglewise.ai/threats/cve-2026-51219-mz-automation-lib60870-heap-buffer-overflow-in-cs104-server)