CVE-2021-39235: Incorrect permissions in Apache Ozone

The vulnerability stems from missing access mode validation in block token verification. The primary suspect is the BlockTokenVerifier class which handles token validation - if it doesn't check the access mode parameter, read tokens would be accepted for write operations. The OzoneManagerProtocolServerSideTranslatorPB is included as it handles client RPCs and might propagate the missing validation. The confidence is high for the core verification function based on the vulnerability pattern described, and medium for the RPC handler due to indirect involvement.