{"id":"CVE-2021-34359","aliases":["EUVD-2021-21019","GHSA-2cm8-2mh8-q729"],"status":"published","title":"Stored XSS Vulnerability in Proxy Server","description":"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","severity":{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00623,"percentile":0.50205,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2022-02-25T06:10:10Z","modified":"2026-06-17T03:55:43Z","products":[{"vendor":"qnap","product":"nas_proxy_server"},{"vendor":"qnap systems inc.","product":"proxy server"}],"references":[{"url":"https://www.qnap.com/en/security-advisory/qsa-22-04","tags":["x_refsource_MISC","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-34359"},{"url":"https://github.com/advisories/GHSA-2cm8-2mh8-q729"}],"sources":{"cve":[{"id":"CVE-2021-34359","title":"Stored XSS Vulnerability in Proxy Server","description":"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","status":"published","published":"2022-02-25T06:10:10.788Z","modified":"2024-09-17T01:12:01.133Z","cvss":[{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:33:11.244759Z"}],"euvd":[{"id":"EUVD-2021-21019","description":"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","status":"published","published":"2022-02-25T06:10:10Z","modified":"2024-09-17T01:12:01Z","cvss":[{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:L/A:N","level":"medium"}],"updated_at":"2026-11-03T00:28:51.722495Z"}],"ghsa":[{"id":"GHSA-2cm8-2mh8-q729","title":"A cross-site scripting (XSS) vulnerability has been reported to affect QNAP device running Proxy...","description":"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","status":"published","published":"2022-02-26T00:00:45Z","modified":"2023-02-03T05:06:18Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:53:52.731364Z"}],"nvd":[{"id":"CVE-2021-34359","description":"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","status":"published","published":"2022-02-25T06:15:06.72Z","modified":"2026-06-17T03:55:43.057Z","cvss":[{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:L/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":3.5,"vector":"AV:N/AC:M/Au:S/C:N/I:P/A:N","level":"low","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:07:05.198719Z"}]}}