libsepol is vulnerable to denial of service. The CIL compiler in SELinux has a heap-based buffer over-read in ebitmap_match_any (called indirectly from cil_check_neverallow). This occurs because there is sometimes a lack of checks for invalid statements in an optional block.
access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.5_release_notes/
access.redhat.com/errata/RHSA-2021:4513
access.redhat.com/security/updates/classification/#moderate
bugs.chromium.org/p/oss-fuzz/issues/detail?id=32675
bugzilla.redhat.com/show_bug.cgi?id=1979668
github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-585.yaml
github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a405521
lists.fedoraproject.org/archives/list/[email protected]/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ@mail.gmail.com/T/