---
title: "CVE-2021-36085\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2021-36085?format=md
keywords: index, follow
---

# CVE-2021-36085

Publication date 1 July 2021

Last updated 25 August 2025

---

Ubuntu priority

**Low**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**3.3 · Low**

[Score breakdown](https://ubuntu.com/security/CVE-2021-36085?format=md#impact-score)

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## 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).

### From the Ubuntu Security Team

sbeattie> AppArmor is the default LSM in Ubuntu, issue only affects
compilation of selinux policy
sbeattie> trusty version predates the introduction of CIL

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| libsepol | 22.04 LTS jammy | Not affected |
| 21.10 impish | Fixed 3.1-1ubuntu2.1 |
| 21.04 hirsute | Ignored end of life |
| 20.10 groovy | Ignored end of life |
| 20.04 LTS focal | Fixed 3.0-1ubuntu0.1 |
| 18.04 LTS bionic | Fixed 2.7-1ubuntu0.1 |
| 16.04 LTS xenial | Fixed 2.4-2ubuntu0.1~esm1  Ubuntu Pro |
| 14.04 LTS trusty | Not affected |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2021-36085?format=md#patch-details)

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### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| libsepol | * Upstream:   [2d35fcc](https://github.com/SELinuxProject/selinux/commit/2d35fcc7e9e976a2346b1de20e54f8663e8a6cba) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

3.3 · Low

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Local |
  | Attack complexity | Low |
  | Privileges required | Low |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | None |
  | Integrity impact | None |
  | Availability impact | Low |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 3.3 · Low |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-36085)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2021-36085)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2021-36085)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2021-36085)

### Related Ubuntu Security Notices (USN)

+ [USN-5391-1](https://usn.ubuntu.com/USN-5391-1)
+ libsepol vulnerabilities
+ 27 April 2022

### Other references

* <https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-421.yaml>
* <https://www.cve.org/CVERecord?id=CVE-2021-36085>