CSRF Bypass in Proxy Server

published 2022-05-26 4y ago modified 2026-06-17 4mo ago also EUVD-2021-21020

cvss: 5.3; 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 41%
public exploits: 0; none known

A cross-site request forgery (CSRF) 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 QuTS hero h5.0.0: Proxy Server 1.4.3 ( 2022/01/18 ) and later QuTScloud c4.5.6: Proxy Server 1.4.2 ( 2021/12/30 ) and later

Patch / fix

fixed in 1

QNAP Systems Inc. Proxy Server 1.4.2 ( 2021/12/30 ), 1.4.3 ( 2022/01/18 )

Is CVE-2021-34360 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Exploit prediction

0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
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. Proxy Server

Classification

Weakness

CWE-352 Cross-Site Request Forgery

References

qnap.com /en/security-advisory/qsa-22-18
vendor-advisory

Sources

CVE List CVE-2021-34360
NVD CVE-2021-34360

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.