GRUB2 contains a race condition leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.4epss 1.0%
exploitation probability
1.0%top 41% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Affected products
Ubuntu · grub2 in UbuntuReferences
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.htmlhttps://access.redhat.com/security/vulnerabilities/grub2bootloaderhttps://lists.gnu.org/archive/html/grub-devel/2020-07/msg00034.htmlhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200011https://security.gentoo.org/glsa/202104-05https://security.netapp.com/advisory/ntap-20200731-0008/https://usn.ubuntu.com/4432-1/https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/GRUB2SecureBootBypasshttps://www.debian.org/security/2020/dsa-4735https://www.debian.org/security/2020-GRUB-UEFI-SecureBoothttps://www.eclypsium.com/2020/07/29/theres-a-hole-in-the-boot/