CVE-2021-36085

LOWNVD 3.33.3—

3.3

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).

CVSS v3: 3.3
EG Score: 3.3(medium)
EPSS: 7.0%
KEV: Not listed

Published

July 1, 2021

Last Modified

November 3, 2025

References (10)

cve@mitrehttps://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31124
cve@mitrehttps://github.com/SELinuxProject/selinux/commit/2d35fcc7e9e976a2346b1de20e54f8663e8a6cba
cve@mitrehttps://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-421.yaml
cve@mitrehttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
af854a3a-2127-422b-91ae-364da2661108https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31124
af854a3a-2127-422b-91ae-364da2661108https://github.com/SELinuxProject/selinux/commit/2d35fcc7e9e976a2346b1de20e54f8663e8a6cba
af854a3a-2127-422b-91ae-364da2661108https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-421.yaml
af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2024/10/msg00021.html
af854a3a-2127-422b-91ae-364da2661108https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/
af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20250207-0004/

Patch Availability(2)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	sepol-utils (3.0-1ubuntu0.1) @ focal	2026-05-26	ubuntu
redhat	libsepol-0:2.9-3.el8	2021-11-09	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-416Use After Free

All Vendor Advisories

(2)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 12× in last 7d / 20× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

2026-06-08 14:15 UTCEPSS rescore
2026-06-08 14:15 UTCEPSS rescore
2026-06-07 15:23 UTCEPSS rescore
2026-06-07 15:23 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-06 13:46 UTCEPSS rescore
2026-06-05 22:45 UTCEPSS rescore
2026-06-05 06:09 UTCEPSS rescore
2026-06-05 06:09 UTCEPSS rescore
2026-06-04 13:10 UTCEPSS rescore
2026-06-04 13:10 UTCEPSS rescore
2026-06-02 20:11 UTCEPSS rescore
2026-06-02 20:11 UTCEPSS rescore
2026-06-01 13:50 UTCEPSS rescore
2026-06-01 13:50 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 00:15 UTCEPSS rescore
2026-05-31 00:15 UTCEPSS rescore

Frequently asked(5)

What is CVE-2021-36085?

CVE-2021-36085 is a low vulnerability published on July 1, 2021. The CIL compiler in SELinux 3.2 has a use-after-free in cilverifyclassperms (called from verifymappermclassperms and hashtabmap).

When was CVE-2021-36085 disclosed?

CVE-2021-36085 was first published in the National Vulnerability Database on July 1, 2021, with the most recent update on November 3, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-36085 actively exploited?

CVE-2021-36085 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 7.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-36085?

CVE-2021-36085 has a CVSS v3 base score of 3.3 (NVD).

How do I remediate CVE-2021-36085?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-36085, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-36085

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CVE-2021-36085

Published

Last Modified

References (10)

Patch Availability(2)

Weakness Classification(1)

All Vendor Advisories

Data Freshness Timeline

Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-36085?

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CVE-2021-36085

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🔄 Last Modified

🔗 References (10)

Patch Availability(2)

Weakness Classification(1)

All Vendor Advisories

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-36085?

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