SB2021120822 - Denial of service in yubihsm-shell



SB2021120822 - Denial of service in yubihsm-shell

Published: December 8, 2021

Security Bulletin ID SB2021120822
Severity
Low
Patch available
YES
Number of vulnerabilities 1
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 1 security vulnerability.


1) Out-of-bounds write (CVE-ID: CVE-2021-43399)

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

The vulnerability exists due to a boundary error in the yh_com_sign_ssh_certificate() function of libyubihsm in YubiHSM 2 SDK. A local user can pass specially crafted input via the ‘certify’ command to yubihsm-shell or via the “-a sign-ssh-certificate” command-line flag and crash the running process.


Remediation

Install update from vendor's website.