CVE-2026-56758 MZ Automation libiec61850 Out-of-bounds Read
An attacker can trigger an out-of-bounds read in the ACSE layer during MMS connection establishment, potentially causing crashes or leaking heap memory.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-56758?
CVE-2026-56758 is a medium-severity memory corruption vulnerability in MZ Automation GmbH libiec61850, published on 30 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
The ACSE layer contains a flaw in the processing of AARQ PDUs during MMS connection establishment. When parsing certain fields within the calling AP title, an attacker controlled length value of zero or one may cause the parser to read past the end of a heap buffer.
Weakness: CWE-125
Which versions are affected by CVE-2026-56758?
How do I fix CVE-2026-56758?
No fix has been published for CVE-2026-56758 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-56758 being exploited?
There is no known exploitation of CVE-2026-56758 in the wild and no public exploit code.
Sources
Also known as GHSA-fvf5-gmx7-5jwx.