High severity · published Jul 23, 2026
CVE-2026-50039
Stack-based Buffer Overflow in MZ Automation libIEC61850
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
The affected product is vulnerable to a stack-based buffer overflow, which may allow an attacker to cause a memory corruption via a Read Request.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libIEC61850 · MZ Automation
1.0.0 through 1.6.1 · source: vendor
In the news
VulnerabilityHigh
MZ Automation libIEC61850
View CSAF
Summary
Successful exploitation of these vulnerabilities could allow an unauthenticated network-adjacent attacker to crash critical IEC 61850 services or execute arbitrary code, disrupting or compromising protection, visibility, and control functions.
The following versions of MZ Automation libIEC61850 are affected:
libIEC61850 >=v1.0.0|<=v1.6.1
CVSS
Vendor
Equipment
Vulnerabilities
v3 8.1
MZ Automation
MZ Automation libIEC61850
Stack-based Buffer Overflow, Heap-based Buffer Overflow, Improper Handling of Syntactically Invalid Structure, NULL Pointer Dereference
Background
Critical Infrastructure Sectors: Critical Manufacturing, Energy, Transportation Systems
Countries/Areas Deployed: Worldwide
Company Headquarters Location: Germany
Vulnerabilities
Expand All +
CVE-2026-50039
The affected product is vulnerable to a stack-based buffer overflow, which may allow an attacker to cause a memory corruption via a ReadRequest.
View CVE Details
Affected Products
MZ Automation libIEC61850
Vendor: MZ Automation
Product Version: MZ Automation libIEC61850: >=v1.0.0|<=v1.6.1
Product Status: known_affected
Remediations
Vendor fix MZ Automation recommends updating to the latest build of the libIEC61850 standard. Documentation can be found at https://github.com/mz-automation/libiec61850. https://github.com/mz-automation/libiec61850
R...
Jul 23, 2026·CISA Advisories
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-50039
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-50039
www.cisa.gov
https://www.cisa.gov/news-events/ics-advisories/icsa-26-204-06
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