CVE-2021-34343 json
Buffer Overflow Vulnerability in QTS, QuTS hero, and QuTScloud
published 2021-09-10 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21003
- cvss
- 6.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.9%
- EPSS 1.9% chance of exploitation in 30 days, percentile 80%
- public exploits
- 0
- none known
Summary
A stack buffer overflow vulnerability has been reported to affect QNAP device running QTS, QuTScloud, QuTS hero. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of QTS, QuTScloud, QuTS hero: QTS 4.5.4.1715 build 20210630 and later QTS 5.0.0.1716 build 20210701 and later QuTScloud c4.5.6.1755 and later QuTS hero h4.5.4.1771 build 20210825 and later
Patch / fix
- QNAP Systems Inc. QTS 4.5.4.1715 build 20210630, 5.0.0.1716 build 20210701
- QNAP Systems Inc. QuTScloud c4.5.6.1755
- QNAP Systems Inc. QuTS hero h4.5.4.1771 build 20210825
Exploit prediction
1.95% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.0 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:H |
| NVD | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 6.5 | AV:N/AC:L/Au:S/C:P/I:P/A:P |
Affected products
- QNAP Systems Inc. QTS
- QNAP Systems Inc. QuTScloud
- QNAP Systems Inc. QuTS hero
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
qnap.com
/en/security-advisory/qsa-21-33
vendor-advisory
Sources
- CVE List CVE-2021-34343
- NVD CVE-2021-34343
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