Intel to release Management Engine Lock to Prevent Disabling,Rollback

It's been an interesting month for users as we've discovered that the most widely-used OS in the world could be one most of us had never even heard anything about before. Intel's Management Engine, a full-fledged computer inside Intel CPUs, runs on MINIX, and after it was outed that Intel's CPUs ran on it, multiple issues have been found with the approach, which has moved Intel towards outing a detection tool.

Intel is seemingly poising to move towards a full hardware lock of the Management Engines' capabilities, thus ensuring it can't be disabled. And even if Intel does send out firmware fixes for its already deployed CPUs with ME integration, the fact remains that the memory pool where the firmware is written is, well, re-writable - given enough access, miscreants could simply re-flash the ME to an earlier, vulnerable version, and thus acquire God Mode access to a victim's computer. To tackle both issues, Intel is moving towards a hardware lock of their ME.

A recent confidential Intel Technical Advisory posted to GitHub stated that starting with ME version 12, the chip's Security Version Number (SVN), which gets incremented with updates to prevent rollbacks, "will be saved permanently in Field Programmable Fuses (FPFs) as a means to mitigate physically downgrading Intel ME [firmware] to a lower SVN." FPFs, once set, become read-only memory (ROM) and can't be so easily altered. providing Intel with a way to validate firmware versions in order to avoid a version rollback.

However, Purism, a company which has made its business to sell privacy-focused Librem laptops in which the Intel Management Engine has been (mostly) disabled, said that while the move was bound to improve security, it didn't fix the fundamental flaws in Intel's ME integration. Purism founder Todd Weaver told The Register that "The ME [Management Engine] hardware still ships on all Intel CPUs; the ME firmware (where this Positive Technologies security exploit is at) is still required by Intel," he said. "If users do not want the ME at all, there is no current Intel based CPU option."