CVE-2021-38689
QNAP
- Published
- 14 January 2022
- Last modified
- 17 June 2026
- CVSS
- 9.8 v3.1
- Severity
- critical
- EPSS
- 1.3% (68th pct)
- CISA KEV
- Not listed
- NVD status
- Modified
- Weaknesses
- CWE-120, CWE-787
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
A stack buffer overflow vulnerability has been reported to affect QNAP device running QVR Elite, QVR Pro, QVR Guard. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of QVR Elite, QVR Pro, QVR Guard: QuTS hero h5.0.0: QVR Elite 2.1.4.0 (2021/12/06) and later QuTS hero h4.5.4: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 5.0.0: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 4.5.4: QVR Elite 2.1.4.0 (2021/12/06) and later QTS 4.5.4: QVR Pro 2.1.3.0 (2021/12/06) and later QTS 5.0.0: QVR Pro 2.1.3.0 (2021/12/06) and later QTS 4.5.4: QVR Guard 2.1.3.0 (2021/12/06) and later QTS 5.0.0: QVR Guard 2.1.3.0 (2021/12/06) and later
Exploitation
Not listed in the CISA Known Exploited Vulnerabilities catalogue as of 2026.09.04. That is an absence of confirmed public exploitation, not evidence that exploitation has not occurred. EPSS models a 1.3% probability of exploitation activity in the next 30 days.
Affected products
| Product | Vendor | Type | Versions named |
|---|---|---|---|
| QVR Elite | QNAP | Video management software | < 2.1.4.0 |
| QVR Guard | QNAP | Video management software | < 2.1.3.0 |
| QVR Pro | QNAP | Video management software | < 2.1.3.0, < 2.7.4.1485, >= 2.7.1.1259 |
References
Vendor advisory and patch
- https://www.qnap.com/en/security-advisory/qsa-21-59
- https://www.qnap.com/en/security-advisory/qsa-21-59
Record assembled from NVD, CISA KEV 2026.09.04 and FIRST EPSS 2026-09-04. Affected products are those NVD's CPE configuration names that fall inside this site's scope; a CVE may affect products outside it.