CVE-2021-38686
Improper Authentication Vulnerability in VioStor
- Published
- Updated
- Reserved
- Assigned by
- qnap
Description
An improper authentication vulnerability has been reported to affect QNAP device, VioStor. If exploited, this vulnerability allows attackers to compromise the security of the system. We have already fixed this vulnerability in the following versions of QVR: QVR FW 5.1.6 build 20211109 and later
Timeline
ID reserved
By qnap
- 4 months later
· 4 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| qnapCNA (assigner) | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.97% · top 38% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Weakness
Affected products
- affected unspecified – < QVR FW 5.1.6 build 20211109
What to do
Solution: We have already fixed this vulnerability in the following versions of QVR: QVR FW 5.1.6 build 20211109 and later
References (1)
- https://www.qnap.com/en/security-advisory/qsa-21-52 (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-2021-38686)Record last updated .