CVE-2021-28806 json
DOM-Based XSS Vulnerability in QTS and QuTS hero
published 2021-06-03 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-15462
- cvss
- 5.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 43%
- public exploits
- 0
- none known
Summary
A DOM-based XSS vulnerability has been reported to affect QNAP NAS running QTS and QuTS hero. If exploited, this vulnerability allows attackers to inject malicious code. This issue affects: QNAP Systems Inc. QTS versions prior to 4.5.3.1652 Build 20210428. QNAP Systems Inc. QuTS hero versions prior to h4.5.2.1638 Build 20210414. QNAP Systems Inc. QuTScloud versions prior to c4.5.5.1656 Build 20210503. This issue does not affect: QNAP Systems Inc. QTS 4.3.6; 4.3.3.
Patch / fix
- QNAP Systems Inc. QTS 4.3.3, 4.3.6, 4.5.3.1652 Build 20210428
- QNAP Systems Inc. QuTS hero h4.5.2.1638 Build 20210414
- QNAP Systems Inc. QuTScloud c4.5.5.1656 Build 20210503
Exploit prediction
0.51% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N |
| NVD | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 3.5 | AV:N/AC:M/Au:S/C:N/I:P/A:N |
Affected products
- QNAP Systems Inc. QTS
- QNAP Systems Inc. QuTS hero
- QNAP Systems Inc. QuTScloud
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
qnap.com
/zh-tw/security-advisory/qsa-21-22
vendor-advisory
Sources
- CVE List CVE-2021-28806
- NVD CVE-2021-28806
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