Does anyone else experience the Ubuntu Kernel Malfunction: “Total Memory Encryption” Intel-MKTME bypass.

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Ubuntu 23.10 (and below)
Linux Kernel 6.2 (and below)
Grub 2 - 9.10 (and below)

Note: Including LTS versions.

Briefing:
This technology encrypts the platform's entire memory with multiple encryption keys. Intel® Total Memory Encryption (Intel® TME), when enabled via BIOS configuration, ensures that all memory accessed from the Intel processor is encrypted.

Acknowledgment:
“kernel: x86/mktme: No known encryption algorithm is supported:” (random numerical value for each instance here) i.e., “0x6”

Details:
During installation and after, a prompt displays after the grub display, flashing the above acknowledged quoted dialog. This does not happen on other operating systems such as Fedora, or Kali, I have tried multiple flavors based on either major platform. This issue is persistent and has been relevant for a few years now, I first noticed it on 20.04, hoping this update was finally noticed by someone who gave a care to report or have this looked into. Disabling TME is not a resolution.

== MKTME-Provided Mitigations ==

MKTME adds a few mitigations against attacks that are not mitigated when using TME alone. The first set are mitigations against software attacks that are familiar today:

 * Kernel Mapping Attacks: information disclosures that leverage the kernel direct map are mitigated against disclosing user data.
 * Freed Data Leak Attacks: removing an encryption key from the hardware mitigates future user information disclosure.

The next set are attacks that depend on specialized hardware, such as an “evil DIMM” or a DDR interposer:

 * Cross-Domain Replay Attack: data is captured from one domain (guest) and replayed to another at a later time.
 * Cross-Domain Capture and Delayed Compare Attack: data is captured and later analyzed to discover secrets.
 * Key Wear-out Attack: data is captured and analyzed in order to weaken the AES encryption itself.

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Bernard Stafford (bernard010) said :
#1

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