0adec29674
The commit ab2e53c8a (grub-mkconfig: Honor a symlink when generating configuration by grub-mkconfig) has inadvertently discarded umask for creating grub.cfg in the process of running grub-mkconfig. The resulting wrong permission (0644) would allow unprivileged users to read GRUB configuration file content. This presents a low confidentiality risk as grub.cfg may contain non-secured plain-text passwords. This patch restores the missing umask and sets the creation file mode to 0600 preventing unprivileged access. Fixes: CVE-2021-3981 Signed-off-by: Michael Chang <mchang@suse.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This is GRUB 2, the second version of the GRand Unified Bootloader. GRUB 2 is rewritten from scratch to make GNU GRUB cleaner, safer, more robust, more powerful, and more portable. See the file NEWS for a description of recent changes to GRUB 2. See the file INSTALL for instructions on how to build and install the GRUB 2 data and program files. See the file MAINTAINERS for information about the GRUB maintainers, etc. If you found a security vulnerability in the GRUB please check the SECURITY file to get more information how to properly report this kind of bugs to the maintainers. Please visit the official web page of GRUB 2, for more information. The URL is <http://www.gnu.org/software/grub/grub.html>. More extensive documentation is available in the Info manual, accessible using 'info grub' after building and installing GRUB 2. There are a number of important user-visible differences from the first version of GRUB, now known as GRUB Legacy. For a summary, please see: info grub Introduction 'Changes from GRUB Legacy'