Known exploited vulnerability
CVE-2021-28799
The short answer
CVE-2021-28799 affects QNAP Systems Inc. HBS 3 and is rated critical (CVSS 9.8). CISA added it to the Known Exploited Vulnerabilities catalog on 2022-03-31: attackers are using it, so patch it first.
What it is
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 .
Weakness: CWE-285.
Severity
9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploited (CISA KEV)
Yes, since Mar 31, 2022
Federal due date Apr 21, 2022
EPSS, next 30 days
78%
Higher than 100% of scored CVEs
How it can be exploited
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
What CISA says to do
Apply updates per vendor instructions.
Affected products
HBS 3, HBS 2, HBS 1.3. NVD's record lists the exact affected versions.
References
- www.qnap.com/en/security-advisory/QSA-21-13 Vendor Advisory
- www.qnap.com/en/security-advisory/QSA-21-13 Vendor Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-28799 US Government Resource
Questions
Is CVE-2021-28799 being exploited?
Yes. CISA added CVE-2021-28799 to its Known Exploited Vulnerabilities catalog on 2022-03-31, with a federal remediation due date of 2022-04-21. CISA lists it as used in ransomware campaigns.
How do I fix CVE-2021-28799?
CISA's required action: Apply updates per vendor instructions.
From NVD, CISA KEV, FIRST EPSS and OSV.dev, checked . Status on NVD: Analyzed. The description is NVD's text, quoted as published.
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