Actively exploited in the wild
QNAP NAS Improper Authorization Vulnerability
QNAP - Network Attached Storage (NAS) · Listed in the CISA KEV since 2022-03-31. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2021-28799
CriticalCVSS 10.0KEVSummary
An improper authorization vulnerability has been reported in QNAP NAS running HBS 3 (Hybrid Backup Sync). If exploited, the vulnerability allows remote attackers to log in to a device without proper authorization.
Risk Assessment
An unauthenticated remote attacker could gain access to the QNAP NAS device interface, potentially leading to data theft or further privilege escalation within the organization's network.
Recommendation
Update HBS 3 to at least v16.0.0415 (QTS 4.5.2), v3.0.210412 (QTS 4.3.6), v3.0.210411 (QTS 4.3.4/4.3.3), v16.0.0419 (QuTS hero h4.5.1), or v16.0.0419 (QuTScloud c4.5.1~c4.5.4). If updating is not possible, restrict network access to the HBS 3 service.
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Original NVD description (English source)
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 .