Overview
Microsoft Windows AppX Installer contains a spoofing vulnerability which has a high impacts to confidentiality, integrity, and availability.
https://nvd.nist.gov/vuln/detail/CVE-2021-43890
Key Details
| Property | Value |
|---|---|
| CVE ID | CVE-2021-43890 |
| Vendor / Product | Microsoft — Windows |
| NVD Published | 2021-12-15 |
| NVD Last Modified | 2026-02-25 |
| CVSS 3.1 Score | 7.1 |
| CVSS 3.1 Vector | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H |
| Severity | HIGH |
| CISA KEV Added | 2021-12-15 |
| CISA KEV Deadline | 2021-12-29 |
| Known Ransomware Use | ⚠️ Yes |
CVSS 3.1 Breakdown
Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Required Action
CISA BOD 22-01 Deadline: 2021-12-29.
Apply updates per vendor instructions.
Timeline
| Date | Event |
|---|---|
| 2021-12-15 | Added to CISA Known Exploited Vulnerabilities catalog |
| 2021-12-29 | CISA BOD 22-01 remediation deadline |
References
| Resource | Type |
|---|---|
| NVD — CVE-2021-43890 | Vulnerability Database |
| CISA KEV Catalog Entry | US Government |