HOMEVULNERABILITIESCVE-2021-36085
LOW

CVE-2021-36085

CWE-416Published: July 1, 2021· Updated: Jun 17, 2026

3.3
CVSS v3.1

Official Description

The CIL compiler in SELinux 3.2 has a use-after-free in __cil_verify_classperms (called from __verify_map_perm_classperms and hashtab_map).

NVD Source

Technical Analysis

CVE-2021-36085 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

From a weakness classification perspective (CWE-416): Use-after-free vulnerabilities involve accessing memory after it has been freed, often enabling arbitrary code execution.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityLow
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Affected Vendors & Products

Fedora1 product(s)
fedora
selinux_project1 product(s)
selinux
Source: NVD CPE · 2 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31124
PATCHhttps://github.com/SELinuxProject/selinux/commit/2d35fcc7e9e976a2346b1de20e54f8663e8a6cba
PATCHhttps://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31124
PATCHhttps://github.com/SELinuxProject/selinux/commit/2d35fcc7e9e976a2346b1de20e54f8663e8a6cba
ADVISORYhttps://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-421.yaml
ADVISORYhttps://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-421.yaml

All References (10)

→
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31124Exploit · Issue Tracking · Patch · Third Party Advisory
→
https://github.com/SELinuxProject/selinux/commit/2d35fcc7e9e976a2346b1de20e54f8663e8a6cbaPatch · Third Party Advisory
→
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-421.yamlThird Party Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
→
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31124Exploit · Issue Tracking · Patch · Third Party Advisory
→
https://github.com/SELinuxProject/selinux/commit/2d35fcc7e9e976a2346b1de20e54f8663e8a6cbaPatch · Third Party Advisory
→
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-421.yamlThird Party Advisory
→
https://lists.debian.org/debian-lts-announce/2024/10/msg00021.html
→
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
→
https://security.netapp.com/advisory/ntap-20250207-0004/

Quick Facts

CVE IDCVE-2021-36085
CVSS Score3.3 / 10
SeverityLOW
WeaknessCWE-416
CISA KEVNo
Affected2 vendor(s)
PublishedJul 1, 2021

Related CVEs (CWE-416)

CVE-2010-3252
10.0
CVE-2012-1972
10.0
CVE-2026-13782
10.0
CVE-2010-3116
10.0
CVE-2011-0982
10.0
CVE-2012-1973
10.0

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2021-36085 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
← All Vulnerabilities·Search for CVE-2021-36085·NVD