CVE-2022-3675 Information

Description

Fedora CoreOS supports setting a GRUB bootloader password using a Butane config. When this feature is enabled GRUB requires a password to access the GRUB command-line modify kernel command-line arguments or boot non-default OSTree deployments. Recent Fedora CoreOS releases have a misconfiguration which allows booting non-default OSTree deployments without entering a password. This allows someone with access to the GRUB menu to boot into an older version of Fedora CoreOS reverting any security fixes that have recently been applied to the machine. A password is still required to modify kernel command-line arguments and to access the GRUB command line.

Reference

https://docs.fedoraproject.org/en-US/fedora-coreos/grub-password/ https://lists.fedoraproject.org/archives/list/coreos-status@lists.fedoraproject.org/thread/NHUCNH5Y4UH5DPUCXISYXXVA563TLFEJ/ https://github.com/coreos/fedora-coreos-tracker/issues/1333