CVE-2026-18784: o6 OPEN62541

Medium severity, CVSS 5.3. EPSS: 0.2% chance of exploitation in the next 30 days.

A vulnerability was found in o6 open62541 up to 1.5.5. This issue affects the function UA_Client_readNodeClassAttribute of the file src/client/ua_client_highlevel.c. Performing a manipulation results in heap-based buffer overflow. Attacking locally is a requirement. The exploit has been made public and could be used. The project closed the issue report, stating that this is not the official way to report a security vulnerability.

Affected products

• o6 OPEN62541: version 1.5.0 only; version 1.5.1 only; version 1.5.2 only; version 1.5.3 only; version 1.5.4 only; version 1.5.5 only

Published 2026-08-04. Last modified 2026-08-12.