An integer overflow occurs in the UA_Variant arrayDimensions product calculation within the open62541 OPC UA library. When a crafted request includes a large array dimension, the multiplication overflows, causing the library to write beyond the allocated buffer. This out‑of‑bounds write can corrupt adjacent memory, potentially allowing an attacker to corrupt data, gain elevated privileges, or crash the application. The flaw is classified as CWE‑190, which reflects improper handling of integer arithmetic.

All systems that embed the open62541 library from o6 Automation are affected. The vendor has not specified exact version ranges, so any installation that incorporates the vulnerable arrayDimensions logic remains at risk until patched.

The CVSS score of 8.7 denotes high severity. The EPSS score of < 1 % indicates that the likelihood of exploitation is very low, though not zero, and the vulnerability is not listed in the CISA KEV catalog. Based on the description, the likely attack vector is remote over the network to an OPC UA server that uses the vulnerable library; an attacker must craft a request that triggers the overflow. While the risk of widespread exploitation remains uncertain, the high impact and absence of external mitigations warrant prompt attention.