SB2021111158 - Fedora 35 update for libsepol 



SB2021111158 - Fedora 35 update for libsepol

Published: November 11, 2021

Security Bulletin ID SB2021111158
Severity
Low
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 secuirty vulnerabilities.


1) Use-after-free (CVE-ID: CVE-2021-36084)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a use-after-free error within the __cil_verify_classperms() function in CIL compiler in SELinux. A local user can perform a denial of service (DoS) attack.


2) Use-after-free (CVE-ID: CVE-2021-36085)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a use-after-free error within the __cil_verify_classperms() function in CIL compiler in SELinux. A local user can perform a denial of service (DoS) attack.

3) Use-after-free (CVE-ID: CVE-2021-36086)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a use-after-free error within the cil_reset_classpermission() function in CIL compiler in SELinux. A local user can perform a denial of service (DoS) attack.

4) Out-of-bounds read (CVE-ID: CVE-2021-36087)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error in the ebitmap_match_any() function within the CIL compiler in SELinux. A local user can trigger an out-of-bounds read error and perform denial of service attack.


Remediation

Install update from vendor's website.