CVE-2021-28809
Missing Authentication for Critical Function in RTRR Server in HBS3
- Published
- Updated
- Reserved
- Assigned by
- qnap
Description
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
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| qnapCNA (assigner) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 16.1% · top 3.1% of all CVEs (6 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
Affected products
- affected unspecified – < v3.0.210507
- affected unspecified – < v3.0.210506
- affected unspecified – < v3.0.210506
What to do
Solution: 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
References (2)
- https://www.qnap.com/en/security-advisory/qsa-21-19 (opens in a new tab)x_refsource_MISCx_transferred
- https://www.zerodayinitiative.com/advisories/ZDI-21-783/ (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-28809)Record last updated .