Vulnerability identifier: #VU62663

Vulnerability risk: Low

CVSSv3.1: 2.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-36087

CWE-ID: CWE-125

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
selinux
Other software / Other software solutions

Vendor:

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error in the ebitmap_match_any() function within the CIL compiler in SELinux. A local user can trigger an out-of-bounds read error and perform denial of service attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

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

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.