CVE-2021-43882

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

2.57% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 84.9% of scored records. A rank, not a probability.

NVD base score

9.8 (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:H/I:H/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

2021-12-15 14:15Z4 YR AGO

Last updated

2024-08-04 04:10Z2 YR AGO

Reserved

2021-11-16

Assigning CNA

microsoft

Record state

PUBLISHED

Severity

Critical (CVSS 9.0)

CNA CVSS vector

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

Weaknesses

• CWE-295Improper Certificate ValidationBase

Data version

5.1

Document digest

391e251579651d5802409d7580e2ee99a0c23edc2168f2a7c7eb4c2e95428e80

• portal.msrc.microsoft.comhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43882x_refsource_MISC
• www.zerodayinitiative.comhttps://www.zerodayinitiative.com/advisories/ZDI-21-1553/x_refsource_MISC