Critical severity · published May 13, 2021
CVE-2021-28799
Improper Authorization Vulnerability in HBS 3 (Hybrid Backup Sync)
RansomwareIn wildKEV
9.8
CVSS
78.2%
EPSS
Yes
On KEV
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 .
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)78.2% · higher than 100% of CVEs
Exploited in the wildYes
CISA KEVListed Mar 31, 2022
Federal remediation dueApr 21, 2022
Ransomware campaign useKnown
Affected products
Which versions
H3
HBS 3 · QNAP Systems Inc.
before v16.0.0415; before v3.0.210412; before v3.0.210411; before v3.0.210411; before v16.0.0419; before v16.0.0419 · source: vendor
HB
Hybrid Backup Sync · Qnap
before 16.0.0415; before 3.0.210412; before 3.0.210411; before 16.0.0419; before 16.0.0419 · source: NVD
NA
Network Attached Storage (NAS) · QNAP
All versions, or not specified · source: KEV