CVE-2026-65421: CWE-125 in MZ Automation GmbH libiec61850
CVE-2026-65421 is a medium severity vulnerability in MZ Automation GmbH's libiec61850 library. It involves a flaw in the MMS BER decoder where an attacker-supplied length value for fixed-width BER fields (boolean/integer) is not properly validated. This can cause a read past the end of a heap buffer, leading to the termination of the MMS service process and resulting in a denial-of-service condition.
AI Analysis
Technical Summary
The MMS BER decoder in libiec61850 does not validate attacker-supplied length values for fixed-width BER fields such as boolean and integer types. This improper validation leads to an out-of-bounds read past the end of a heap buffer, causing the MMS service process to terminate unexpectedly. The vulnerability is identified as CWE-125 (Out-of-bounds Read) and results in a denial-of-service condition by crashing the affected service.
Potential Impact
Successful exploitation causes the MMS service process to terminate, resulting in a denial-of-service (DoS) condition. There is no impact on confidentiality or integrity as per the CVSS vector. The attack vector is adjacent network (AV:A), requires no privileges (PR:N), and no user interaction (UI:N).
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary mitigation has been documented at this time.
CVE-2026-65421: CWE-125 in MZ Automation GmbH libiec61850
Description
CVE-2026-65421 is a medium severity vulnerability in MZ Automation GmbH's libiec61850 library. It involves a flaw in the MMS BER decoder where an attacker-supplied length value for fixed-width BER fields (boolean/integer) is not properly validated. This can cause a read past the end of a heap buffer, leading to the termination of the MMS service process and resulting in a denial-of-service condition.
CVSS v3.1
Score 6.5medium
Affected software
MZ Automation GmbH
libiec61850
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The MMS BER decoder in libiec61850 does not validate attacker-supplied length values for fixed-width BER fields such as boolean and integer types. This improper validation leads to an out-of-bounds read past the end of a heap buffer, causing the MMS service process to terminate unexpectedly. The vulnerability is identified as CWE-125 (Out-of-bounds Read) and results in a denial-of-service condition by crashing the affected service.
Potential Impact
Successful exploitation causes the MMS service process to terminate, resulting in a denial-of-service (DoS) condition. There is no impact on confidentiality or integrity as per the CVSS vector. The attack vector is adjacent network (AV:A), requires no privileges (PR:N), and no user interaction (UI:N).
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary mitigation has been documented at this time.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- icscert
- Date Reserved
- 2026-07-27T19:32:49.396Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a6bd5b69c2644c7f8d19674
Added to database: 07/30/2026, 22:52:38 UTC
Last enriched: 08/07/2026, 14:51:33 UTC
Last updated: 09/13/2026, 11:25:30 UTC
Views: 62
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