CVE-2021-28809: An improper access control vulnerability has been reported to affect certain legacy versions of HBS 3. If exploited, this vulnerability allows attackers to…

PriorityP266critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

15.80%

96.5th percentile

An improper access control vulnerability has been reported to affect certain legacy versions of HBS 3. If exploited, this vulnerability allows attackers to compromise the security of the operating system.QNAP have already fixed this vulnerability in the following versions of HBS 3: QTS 4.3.6: HBS 3 v3.0.210507 and later QTS 4.3.4: HBS 3 v3.0.210506 and later QTS 4.3.3: HBS 3 v3.0.210506 and later

Affected

4 ranges

Vendor	Product	Version range	Fixed in
qnap	hybrid_backup_sync	< 3.0.210507	3.0.210507
qnap	hybrid_backup_sync	< 3.0.210506	3.0.210506
qnap_systems_inc	hbs_3	>= unspecified < v3.0.210507	v3.0.210507
qnap_systems_inc	hbs_3	>= unspecified < v3.0.210506	v3.0.210506

Detection & IOCsextracted from sources · hover to see the quote

→CVE-2021-28809 affects QNAP HBS 3 on legacy QTS versions; exploitation allows privilege escalation, remote command execution, or unauthorized access to sensitive information on NAS devices without authentication ↗

·Vulnerability only affects legacy HBS 3 versions on QTS 4.3.6 (prior to v3.0.210507), QTS 4.3.4 (prior to v3.0.210506), and QTS 4.3.3 (prior to v3.0.210506); newer QTS versions are not affected ↗

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv2.010.0CRITICALAV:N/AC:L/Au:N/C:C/I:C/A:C

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