CVE-2021-43399

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

1.37% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 70.0% of scored records. A rank, not a probability.

NVD base score

7.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-12-08 18:31Z4 YR AGO

Last updated

2024-08-04 03:55Z2 YR AGO

Reserved

2021-11-04

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-787Out-of-bounds WriteBase

Data version

5.1

Document digest

8abd7c510a83bfbb47a615c3b19e379fe8cdb930b3730124f54bdd18d9de4c3d

• www.yubico.comhttps://www.yubico.com/support/security-advisories/ysa-2021-04/x_refsource_MISC
• blog.inhq.nethttps://blog.inhq.net/posts/yubico-yubihsm-shell-vuln3/x_refsource_MISC