Improper Authentication Vulnerability in VioStor

published 2021-11-26 4y ago modified 2026-06-17 4mo ago also EUVD-2021-25125

cvss: 8.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 62%
public exploits: 0; none known

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

Patch / fix

fixed in 1

QNAP Systems Inc. QVR QVR FW 5.1.6 build 20211109

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Exploit prediction

0.97% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

QNAP Systems Inc. QVR

Classification

Weakness

CWE-287 Improper Authentication

References

qnap.com /en/security-advisory/qsa-21-52
vendor-advisory

Sources

CVE List CVE-2021-38686
NVD CVE-2021-38686

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