CVE-2017-7893: SaltStack Salt allows compromised salt-minions to impersonate the salt-master

The vulnerability stems from inadequate authentication checks in two critical areas: 1) Cryptographic signature verification (salt.crypt.verify_signature) likely failed to properly validate() the master's identity, allowing minions to forge commands. 2) The transport layer (salt.transport.Channel) may have accepted messages from unauthorized sources as master commands. These weaknesses combined would let a compromised minion impersonate the master by bypassing cryptographic authentication and exploiting the trust relationship in the communication channel.