Out-of-bounds read in selinux - CVE-2021-36087
Published: April 27, 2022
Vulnerability identifier: #VU62663
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-36087
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: SELinux Project
Affected software:
selinux
selinux
Detailed vulnerability 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.
How to mitigate CVE-2021-36087
Install update from vendor's website.
Sources
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-585.yaml
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32675
- https://lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ@mail.gmail.com/T/
- https://github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a405521
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/