A method, system, and computer program product for a host software tamper detection and protection service. A secure partition that is isolated from a host operating system of the host system, which may be implemented by firmware of a chipset of the host system, obtains file metadata from the host system and uses the file metadata to identify a first file for examination for tampering. The secure partition obtains data blocks for the first file, communicates with a service via an out-of-band communication channel, and uses information obtained from the service and the data blocks to determine whether the first file has been corrupted. The secure partition obtains the file metadata and the data blocks for the first file without invoking an operating system or file system of the host system.