USN-4628-2: Intel Microcode regression

Severity

Medium

Vendor

Canonical Ubuntu

Description

USN-4628-1 provided updated Intel Processor Microcode. Unfortunately, that update prevented certain processors in the Intel Tiger Lake family from booting successfully. This update reverts the microcode update for the Tiger Lake processor family.

Please note that the ‘dis_ucode_ldr’ kernel command line option can be added in the boot menu to disable microcode loading for system recovery.

We apologize for the inconvenience.

Original advisory details:

Moritz Lipp, Michael Schwarz, Andreas Kogler, David Oswald, Catherine Easdon, Claudio Canella, and Daniel Gruss discovered that the Intel Running Average Power Limit (RAPL) feature of some Intel processors allowed a side- channel attack based on power consumption measurements. A local attacker could possibly use this to expose sensitive information. (CVE-2020-8695)

Ezra Caltum, Joseph Nuzman, Nir Shildan and Ofir Joseff discovered that some Intel(R) Processors did not properly remove sensitive information before storage or transfer in some situations. A local attacker could possibly use this to expose sensitive information. (CVE-2020-8696)

Ezra Caltum, Joseph Nuzman, Nir Shildan and Ofir Joseff discovered that some Intel(R) Processors did not properly isolate shared resources in some situations. A local attacker could possibly use this to expose sensitive information. (CVE-2020-8698)

CVEs contained in this USN include: CVE-2020-8698, CVE-2020-8696, CVE-2020-8695.

Affected Cloud Foundry Products and Versions

Severity is medium unless otherwise noted.

• Xenial Stemcells
  • 315.x versions prior to 315.202
  • 456.x versions prior to 456.129
  • 621.x versions prior to 621.93
  • All other stemcells not listed.

Mitigation

Users of affected products are strongly encouraged to follow the mitigations below. The Cloud Foundry project recommends upgrading the following releases:

• Xenial Stemcells
  • Upgrade 315.x versions to 315.202 or greater
  • Upgrade 456.x versions to 456.129 or greater
  • Upgrade 621.x versions to 621.93 or greater
  • All other stemcells should be upgraded to the latest version available on bosh.io.

History

2020-12-11: Initial vulnerability report published.