---
id: CVE-2026-57446
title: >-
  libIEC61850: Server-side double free in MMS ObtainFile task reuse due to stale
  FILE* handle
summary: >-
  libIEC61850 is an open-source implementation of IEC 61850 client and server
  protocols including MMS, GOOSE, Sampled Values, and R-Session. From 1.6.1
  until 1.6.2, a successful MMS ObtainFile operation closes
  MmsObtainFileTask::fileHandle…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cvssSource: cna
cwe:
  - CWE-415
  - CWE-664
  - CWE-672
vendor: mz-automation
product: libiec61850
affected:
  - 'libiec61850 >= 1.6.1, < 1.6.2'
published: '2026-10-16'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:46:33.549Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-57446'
references:
  - url: >-
      https://github.com/mz-automation/libiec61850/security/advisories/GHSA-cxgr-7v9h-fj9p
    label: >-
      https://github.com/mz-automation/libiec61850/security/advisories/GHSA-cxgr-7v9h-fj9p
  - url: >-
      https://github.com/mz-automation/libiec61850/commit/d86b4a9c7a903641819235e1678b18901518f3cd
    label: >-
      https://github.com/mz-automation/libiec61850/commit/d86b4a9c7a903641819235e1678b18901518f3cd
  - url: 'https://github.com/mz-automation/libiec61850/releases/tag/v1.6.2'
    label: 'https://github.com/mz-automation/libiec61850/releases/tag/v1.6.2'
tags:
  - cve.org
ingestedAt: '2026-10-16T17:24:46.829Z'
---

## Overview

libIEC61850 is an open-source implementation of IEC 61850 client and server protocols including MMS, GOOSE, Sampled Values, and R-Session. From 1.6.1 until 1.6.2, a successful MMS ObtainFile operation closes MmsObtainFileTask::fileHandle but leaves the stale non-NULL value in a task marked MMS_FILE_UPLOAD_STATE_NOT_USED. If a later ObtainFile request reuses that task and destination creation fails, MMS_FILE_UPLOAD_STATE_SEND_OBTAIN_FILE_ERROR_DESTINATION cleanup closes the stale FILE object again. Servers with the MMS file service and ObtainFile enabled can therefore be crashed remotely by the success-then-failure request sequence. This issue is fixed in version 1.6.2.

## Affected

- `libiec61850 >= 1.6.1, < 1.6.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.