open62541 1.5.5 contains a buffer-overflow in the high-level attribute reading logic in src/client/ua_client_highlevel.c. This allows a remote attacker to cause a denial of service.
https://github.com/open62541/open62541/issues/8139
https://github.com/open62541/open62541/blob/v1.5.5/src/client/ua_client_highlevel.c