Intel AMT / ISM / SBT firmware anti-rollback, ME 11.0.25.3001 and 11.0.26.3000: The patched ME firmware does

Impact

The patched ME firmware does not enforce anti-rollback, so a local administrator can downgrade the ME back to an 11.6.x image that is vulnerable to the KEV-listed AMT auth bypass. Operationally this means a node you have already remediated can be silently un-remediated: your fleet inventory says 'patched', the ME says otherwise, and the auth bypass is live again. Because the downgrade lives in the ME region, it survives a host reimage and therefore survives tenant handoff.

Who can reach it

Local root or administrator on the host, using the normal Intel ME firmware update path (HECI/MEI device). No physical access, no ME exploit required - just the vendor's own update tool. Any tenant who has been given real root on a bare-metal node can do this before handing the node back.

What to do

Flash to an ME build that enforces the rollback floor - again an OEM BIOS/ME bundle from Dell/HPE/Lenovo/Supermicro/Gigabyte/Quanta, with a reboot. The durable control is process, not firmware: read back and attest the actual ME firmware version at node reclaim time rather than trusting an inventory record, and block host-side ME update tooling (MEI device access, Intel MEInfo/FWUpdate binaries) inside tenant images.

References