CVE-2020-15706

Priority
Description
GRUB2 contains a race condition in grub_script_function_create() leading to
a use-after-free vulnerability which can be triggered by redefining a
function whilst the same function is already executing, leading to
arbitrary code execution and secure boot restriction bypass. This issue
affects GRUB2 version 2.04 and prior versions.
Ubuntu-Description
Chris Coulson discovered that the GRUB2 function handling code did not
properly handle a function being redefined, leading to a use-after-free
vulnerability. A local attacker could use this to execute arbitrary code
and bypass UEFI Secure Boot restrictions.
Notes
amurraygrub2-signed is not supported in Ubuntu 12.04 ESM (precise/esm) and so marking the priority for grub2 in this release as low
sbeattie809f3a268 script: Avoid a use-after-free when redefining a function during execution
Package
Source: grub2 (LP Ubuntu Debian)
Upstream:needs-triage
Ubuntu 12.04 ESM (Precise Pangolin):needed
Ubuntu 14.04 ESM (Trusty Tahr):released (2.02~beta2-9ubuntu1.20)
Ubuntu 16.04 LTS (Xenial Xerus):released (2.02~beta2-36ubuntu3.26)
Ubuntu 18.04 LTS (Bionic Beaver):released (2.02-2ubuntu8.16)
Ubuntu 20.04 LTS (Focal Fossa):released (2.04-1ubuntu26.1)
Ubuntu 20.10 (Groovy Gorilla):not-affected (2.04-1ubuntu26.1)
Package
Upstream:needs-triage
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):released (1.34.22)
Ubuntu 16.04 LTS (Xenial Xerus):released (1.66.26)
Ubuntu 18.04 LTS (Bionic Beaver):released (1.93.18)
Ubuntu 20.04 LTS (Focal Fossa):released (1.142.3)
Ubuntu 20.10 (Groovy Gorilla):not-affected (1.147)
More Information

Updated: 2020-08-05 04:14:37 UTC (commit 75ee2efd5b1f4456ca1263baf8c308c5218273da)