Zowe CLI

• Breaking: zowe zos-uss (ssh) commands now verify the z/OS SSH server's host key before sending credentials. On first connect you confirm the fingerprint and the key is saved to your ssh profile; a changed key is rejected. Use --insecure to skip verification or --host-key to pin a key. #2813

z/OS Files SDK

• Breaking: The ZosFilesUtils.ensureSafeTempDir function no longer creates missing parent directories recursively; the temp directory's immediate parent must already exist. This avoids a race condition where a recursive mkdir function call could create part of the path before the safety checks ran. #2831

z/OS USS SDK

• Breaking: SshSession now verifies the server's host key before sending credentials, using the hostKey and insecure session properties and an optional interactive hostVerifier hook; an unknown or changed key is rejected. #2813
• Breaking: Shell.isConnectionValid now rejects with a host key error when the host key is untrusted or changed, instead of returning false. #2813