SB2021012639 - Ubuntu update for sudo



SB2021012639 - Ubuntu update for sudo

Published: January 26, 2021 Updated: May 14, 2023

Security Bulletin ID SB2021012639
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) Heap-based buffer overflow (CVE-ID: CVE-2021-3156)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

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:A/U:Clear


The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error in sudo. A local user can pass specially crafted data to the application, trigger heap-based buffer overflow and execute arbitrary code on the target system with root privileges.



Remediation

Install update from vendor's website.