CVE-2021-34359 json
Stored XSS Vulnerability in Proxy Server
published 2022-02-25 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21019
- cvss
- 6.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 50%
- public exploits
- 0
- none known
Summary
A cross-site scripting (XSS) vulnerability has been reported to affect QNAP device running Proxy Server. If exploited, this vulnerability allows remote attackers to inject malicious code. We have already fixed this vulnerability in the following versions of Proxy Server: QTS 4.5.x: Proxy Server 1.4.2 ( 2021/12/30 ) and later
Patch / fix
- QNAP Systems Inc. Proxy Server 1.4.2 ( 2021/12/30 )
Exploit prediction
0.62% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.9 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:L/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. Proxy Server
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
qnap.com
/en/security-advisory/qsa-22-04
vendor-advisory
Sources
- CVE List CVE-2021-34359
- NVD CVE-2021-34359
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