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TI-2021-13398 Aliases CVE-2021-34359GHSA-2cm8-2mh8-q729

Stored XSS Vulnerability in Proxy Server

Priority LOW 31CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.

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

Why it matters now

EPSS 0.00623 50th percentileScored 2026-11-07
Fix Fixed Proxy Server (QNAP Systems Inc.): 1.4.2 ( 2021/12/30 )

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
QNAPProxy Serverbefore 1.4.2 ( 2021/12/30 )1.4.2 ( 2021/12/30 )Patch availableCNA
  • Proxy Server VendorQNAP Affected before 1.4.2 ( 2021/12/30 ) Fixed in 1.4.2 ( 2021/12/30 ) Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:qnap:nas_proxy_server:*:*:*:*:*:*:*:*before 1.4.2VulnerableQNAP
cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:*4.5.1 – 4.5.4Running onQNAP
  • cpe:2.3:a:qnap:nas_proxy_server:*:*:*:*:*:*:*:* Versions before 1.4.2 Vulnerable ·QNAP
  • cpe:2.3:o:qnap:qts:*:*:*:*:*:*:*:* Versions 4.5.1 – 4.5.4 Running on ·QNAP

Remediation

  • Fix · CNA Proxy Server (QNAP Systems Inc.) Fixed in 1.4.2 ( 2021/12/30 )

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    QNAP Systems Proxy Server 1.4.2 ( 2021/12/30 )

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2021-13400 Reflected XSS Vulnerability in Proxy ServerPriority LOW 28
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-34359
  2. 2026-10-03 Alias added: GHSA-2cm8-2mh8-q729
  3. 2026-11-05 EPSS moved to the 50th–90th percentile

References

Advisory 1

  • TI-2017-05273 QNAP NAS application Proxy Server through version 1.2.0 allows remote attackers to run… CVSS 3.0CRITICAL 9.8
  • TI-2021-13399 CSRF Bypass in Proxy Server CVSS 3.1HIGH 8.8
  • TI-2017-05271 QNAP NAS application Proxy Server through version 1.2.0 does not utilize CSRF protections. CVSS 3.0HIGH 8.8
  • TI-2017-05272 Cross-site scripting (XSS) vulnerability in QNAP NAS application Proxy Server through… CVSS 3.0MEDIUM 6.1
  • TI-2021-13400 Reflected XSS Vulnerability in Proxy Server CVSS 3.1MEDIUM 6.1
  • TI-2017-05275 QNAP NAS application Proxy Server through version 1.2.0 does not authenticate requests… CVSS 3.0MEDIUM 5.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences