SB2021052034 - Red Hat Enterprise Linux 8 update for sudo



SB2021052034 - Red Hat Enterprise Linux 8 update for sudo

Published: May 20, 2021

Security Bulletin ID SB2021052034
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 vulnerabilities.


1) Link following (CVE-ID: CVE-2021-23239)

CWE-ID: CWE-59 - Improper Link Resolution Before File Access ('Link Following')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local authenticated user to gain access to sensitive information.

The sudoedit personality of Sudo before 1.9.5 may allow a local unprivileged user to perform arbitrary directory-existence tests by winning a sudo_edit.c race condition in replacing a user-controlled directory by a symlink to an arbitrary path.


2) Link following (CVE-ID: CVE-2021-23240)

CWE-ID: CWE-59 - Improper Link Resolution Before File Access ('Link Following')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local authenticated user to execute arbitrary code.

selinux_edit_copy_tfiles in sudoedit in Sudo before 1.9.5 allows a local unprivileged user to gain file ownership and escalate privileges by replacing a temporary file with a symlink to an arbitrary file target. This affects SELinux RBAC support in permissive mode. Machines without SELinux are not vulnerable.


Remediation

Install update from vendor's website.