grub2 is vulnerable to denial of service (DoS). The vulnerability exists through integer overflow in grub_ext2_read_link.
lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html
lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html
www.openwall.com/lists/oss-security/2021/09/17/2
www.openwall.com/lists/oss-security/2021/09/17/4
www.openwall.com/lists/oss-security/2021/09/21/1
access.redhat.com/errata/RHSA-2020:3223
access.redhat.com/security/updates/classification/#moderate
access.redhat.com/security/vulnerabilities/grub2bootloader
bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-14311
security.gentoo.org/glsa/202104-05
usn.ubuntu.com/4432-1/