CVE-2021-28807

A post-authentication reflected XSS vulnerability has been reported to affect QNAP NAS running Q’center. If exploited, this vulnerability allows remote attackers to inject malicious code. QNAP have already fixed this vulnerability in the following versions of Q’center: QTS 4.5.3: Q’center v1.12.1012 and later QTS 4.3.6: Q’center v1.10.1004 and later QTS 4.3.3: Q’center v1.10.1004 and later QuTS hero h4.5.2: Q’center v1.12.1012 and later QuTScloud c4.5.4: Q’center v1.12.1012 and later

• CWE-79

• https://www.qnap.com/zh-tw/security-advisory/qsa-21-20Vendor Advisory
• https://www.shielder.it/advisories/qnap-qcenter-post-auth-remote-code-execution-via-qpkg/Exploit, Third Party Advisory
• https://www.shielder.it/advisories/qnap-qcenter-virtual-stored-xss/Exploit, Third Party Advisory
• https://www.qnap.com/zh-tw/security-advisory/qsa-21-20Vendor Advisory
• https://www.shielder.it/advisories/qnap-qcenter-post-auth-remote-code-execution-via-qpkg/Exploit, Third Party Advisory
• https://www.shielder.it/advisories/qnap-qcenter-virtual-stored-xss/Exploit, Third Party Advisory

Published

Jun 3, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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