Out-of-bounds Write in o6 Automation GmbH Open62541

In builds with PubSub and JSON enabled, a crafted JSON message can cause the decoder to write beyond a heap-allocated array before authentication, reliably crashing the process and corrupting memory.

Problem type

CWE-787 Out-of-bounds Write

Affected products

o6 Automation GmbH

Open62541

< 1.5-rc2 - AFFECTED

References

cisa.gov

https://www.cisa.gov/news-events/ics-advisories/icsa-26-036-03

government-resource

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-1301

Click to expand

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