CVE-2021-43221: Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability

Severity: medium (CVSS 4.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-11-24 · updated 2026-08-19
Weakness: CWE-94

Description

Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability

Affected products

Microsoft Edge (Chromium): before 96.0.1054.29 — fixed in 96.0.1054.29
Microsoft Edge (Chromium): from 1.0.0.0 before 96.0 1954.29 — fixed in 96.0 1954.29

How to fix

Upgrade to a fixed version: Microsoft Edge (Chromium) 96.0.1054.29; Microsoft Edge (Chromium) 96.0 1954.29. Check the vendor advisory for mitigations.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-43221
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43221

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