CVE-2021-43221

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

1.15% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 66.8% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-08-19.

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

2021-11-24 01:05Z4 YR AGO

Last updated

2026-08-19 16:27Z2 MO AGO

Reserved

2021-11-02

Assigning CNA

microsoft

Record state

PUBLISHED

Severity

Medium (CVSS 4.2)

CNA CVSS vector

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

Weaknesses

No CWE assigned

Data version

5.2

Document digest

a6872eda40cfca06b396b6c6c032513b5ef02b3675e27f3d586440e0fa0b25c0

• msrc.microsoft.comMicrosoft Edge (Chromium-based) Remote Code Execution Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-43221vendor-advisorypatch
• portal.msrc.microsoft.comhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43221x_refsource_MISC