CVE-2021-28799

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Summary

CVECVE-2021-28799
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-05-13 03:15:00 UTC
Updated2023-11-14 19:26:00 UTC
DescriptionAn 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 .

Risk And Classification

EPSS: 0.911460000 probability, percentile 0.996430000 (date 2026-04-01)

CISA KEV: Listed on 2022-03-31; due 2022-04-21; ransomware use Known

Problem Types: NVD-CWE-Other

CISA Known Exploited Vulnerability

VendorQNAP
ProductNetwork Attached Storage (NAS)
NameQNAP NAS Improper Authorization Vulnerability
Required ActionApply updates per vendor instructions.
Noteshttps://nvd.nist.gov/vuln/detail/CVE-2021-28799

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Qnap Hybrid Backup Sync All All All All
Application Qnap Qts 4.3.3 All All All
Application Qnap Qts 4.3.4 All All All
Application Qnap Qts 4.3.6 All All All
Application Qnap Qts 4.5.2 All All All
Operating System Qnap Qts 4.3.6 All All All
Operating System Qnap Qutscloud All All All All
Application Qnap Quts Hero h4.5.1 All All All
Operating System Qnap Quts Hero h4.5.1 All All All

References

ReferenceSourceLinkTags
Improper Authorization Vulnerability in HBS 3 Hybrid Backup Sync - Security Advisory | QNAP MISC www.qnap.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
CISA Known Exploited Vulnerabilities catalog CISA www.cisa.gov kev

Vendor Comments And Credit

Discovery Credit

LEGACY: ZUSO ART

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