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CVE-2021-28799: QNAP NAS Improper Authorization Vulnerability
QNAP Network Attached Storage (NAS) · in CISA KEV since 2022-03-31
2022-03-31added to KEV
2022-04-21federal remediation due date
78.25%EPSS exploit probability (30 days) 99.6th percentile
9.8 CRITICALCVSS 3.1
Knownknown ransomware use
322days from NVD publication to KEV
What it is
QNAP NAS running HBS 3 contains an improper authorization vulnerability which can allow remote attackers to log in to a device.
Required action (CISA)
Apply updates per vendor instructions.
| CWE | CWE-285 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-05-13 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-28799.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.