Out-of-bounds Read in Selinux Project
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.005 (37.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 37.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Selinux Project — versions 3.2
- Fedoraproject Fedora — versions 35
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-585.yaml (Third Party Advisory)
- bugs.chromium.org/p/oss-fuzz/issues/detail (Exploit, Patch, Third Party Advisory, Issue Tracking)
- lore.kernel.org/selinux/CAEN2sdqJKHvDzPnxS-J8grU8fSf32DDtx=kyh84OsCq_Vm+yaQ@mai…
- github.com/SELinuxProject/selinux/commit/340f0eb7f3673e8aacaf0a96cbfcd4d12a4055… (Patch, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2021-36087?
- CVE-2021-36087 is a low-severity vulnerability in Selinux Project, classified under Out-of-bounds Read. CVSS score: 3.3/10. Published 2021-07-01.
- How severe is CVE-2021-36087?
- Low severity. CVSS v3 base score is 3.3 out of 10.
- Is CVE-2021-36087 known to be exploited?
- 8 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.