CVE-2021-38691: qnap systems inc. qvr elite Classic Buffer Overflow
Vulnerability summary
CVE-2021-38691 is a critical (CVSS 9.8) Classic Buffer Overflow vulnerability in qnap systems inc. qvr elite. EPSS estimates a 1.30% chance of exploitation in the next 30 days, higher than 69.9% of scored vulnerabilities.
Timeline
- 14-01-2022PublishedVulnerability first disclosed.
- 17-09-2024Last modifiedVulnerability information updated.
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
CVSS metrics
3 scores · 2 sources · 2 versions- CVE.orgCNA8.1HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HDiffers
EPSS trend
Probability
1.30%
Chance of exploitation in the next 30 days
Percentile
70%
Versus all other CVEs
30-day change
0.00 pp
From 1.30% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.
- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
Affected systems
2 vendors · 6 products