SB2021120822 - Denial of service in yubihsm-shell
Published: December 8, 2021
Security Bulletin ID
SB2021120822
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Partial DoS
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Out-of-bounds write (CVE-ID: CVE-2021-43399)
CWE-ID: CWE-787 - Out-of-bounds write
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
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.