Threats affecting pkg:maven/org.apache.plc4x/plc4j

Apache PLC4X versions from 0.9.0 up to but not including 1.0.0 contain improper verification of cryptographic signatures and improper certificate validation in the OPC UA driver. This flaw allows an attacker positioned between client and server to impersonate the OPC UA server and read, forge, or modify secure-channel traffic, including user credentials. The vulnerability manifests differently across versions, including logging but not enforcing failed signature checks, inverted signature validation logic, acceptance of untrusted server certificates, and defaulting to weak security policies. Version 1.0.0 fixes these issues by correctly verifying signatures, enforcing certificate trust, and requiring stronger security policies.