CVE-2021-36087

Public Exploit

Description

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.

Category

3.3
CVSS
Severity: Low
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.02%
Vendor Advisory fedoraproject.org
Affected: n/a n/a
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2021-36087?
CVE-2021-36087 has been scored as a low severity vulnerability.
How to fix CVE-2021-36087?
To fix CVE-2021-36087, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-36087 being actively exploited in the wild?
It is possible that CVE-2021-36087 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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