CVE-2021-43399

high

Description

The Yubico YubiHSM YubiHSM2 library 2021.08, included in the yubihsm-shell project, does not properly validate the length of some operations including SSH signing requests, and some data operations received from a YubiHSM 2 device.

References

https://www.yubico.com/support/security-advisories/ysa-2021-04/

https://blog.inhq.net/posts/yubico-yubihsm-shell-vuln3/

Details

Source: Mitre, NVD

Published: 2021-12-08

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

EPSS

EPSS: 0.00555