CVE-2021-36086

Publication date 1 July 2021

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

The CIL compiler in SELinux 3.2 has a use-after-free in cil_reset_classpermission (called from cil_reset_classperms_set and cil_reset_classperms_list).

Read the notes from the security team

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	Not affected
	14.04 LTS trusty	Not affected

Notes

sbeattie

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

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
libsepol	Upstream: c49a8ea

Severity score breakdown

Parameter	Value
Base score	3.3 · Low
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	Low
Vector	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

References

Related Ubuntu Security Notices (USN)

USN-5391-1
libsepol vulnerabilities
27 April 2022