Stack Overflow Vulnerability in QVR Elite, QVR Pro and QVR Guard

published 2022-01-14 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-25130

cvss: 8.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 71%
public exploits: 0; none known

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

Patch / fix

fixed in 3

QNAP Systems Inc. QVR Elite 2.1.4.0 (2021/12/06)
QNAP Systems Inc. QVR Pro 2.1.3.0 (2021/12/06)
QNAP Systems Inc. QVR Guard 2.1.3.0 (2021/12/06)

Exploit prediction

1.34% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

QNAP Systems Inc. QVR Elite
QNAP Systems Inc. QVR Pro
QNAP Systems Inc. QVR Guard

Classification

Weakness

CWE-120 Buffer Copy without Checking Size of Input
CWE-787 Out-of-bounds Write

References

qnap.com /en/security-advisory/qsa-21-59
vendor-advisory

Sources

CVE List CVE-2021-38691
NVD CVE-2021-38691

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Summary