A flaw was found in grub2 in versions prior to 2.06. The rmmod implementation allows the unloading of a module used as a dependency without checking if any other dependent module is still loaded leading to a use-after-free scenario. This could allow arbitrary code to be executed or a bypass of Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-25632
Reference (s):
- FEDORA:FEDORA-2021-cab258a413
- URL: https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH3WXZBHT2R/
- GENTOO:GLSA-202104-05
- URL: https://security.gentoo.org/glsa/202104-05
- https://bugzilla.redhat.com/show_bug.cgi?id=1879577