CRITICAL CISA KEV

CVE-2021-28799

CVSS v3

9.8

CRITICAL

EPSS Score

91.1 %

exploit probability

CISA KEV

Yes

known exploited

Exploitation

—

SSVC status

Description

An improper authorization vulnerability has been reported to affect QNAP NAS running HBS 3 (Hybrid Backup Sync. ) If exploited, the vulnerability allows remote attackers to log in to a device. This issue affects: QNAP Systems Inc. HBS 3 versions prior to v16.0.0415 on QTS 4.5.2; versions prior to v3.0.210412 on QTS 4.3.6; versions prior to v3.0.210411 on QTS 4.3.4; versions prior to v3.0.210411 on QTS 4.3.3; versions prior to v16.0.0419 on QuTS hero h4.5.1; versions prior to v16.0.0419 on QuTScloud c4.5.1~c4.5.4. This issue does not affect: QNAP Systems Inc. HBS 2 . QNAP Systems Inc. HBS 1.3 .

CISA Known Exploited Vulnerability

Date Added: 2022-03-31
Patch Due Date: 2022-04-21
Ransomware Use: Known

Technical details

Published: 2021-05-13

Frequently asked questions

What is CVE-2021-28799?

Is CVE-2021-28799 actively exploited?

Yes. CVE-2021-28799 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 2022-04-21.

What is the CVSS score for CVE-2021-28799?

CVE-2021-28799 has a CVSS v3 base score of 9.8 (CRITICAL severity).

Is CVE-2021-28799 affecting your environment?

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