CVE-2021-36087

The CIL compiler in SELinux 3.2 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.

CVSS 3.1

3.3CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

EPSS

0.5% chance of exploitation in the next 30 days; higher than 41% of CVEs (scores of 2026-10-25)

CWE

CWE-125

Published

2021-07-01

Modified

2026-10-14

Record from

the NVD, synced 2026-10-19

Affected

• fedoraproject:fedora
• selinux_project:selinux

References

• https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32675
• https://github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a405521
• https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-585.yaml
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
• https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ%40mail.gmail.com/T/

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