CVE-2021-28807

Public Exploit
Post-Authentication Reflected XSS Vulnerability in Q'center

Description

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

Remediation

Solution:

  • 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

Category

7.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.15% Top 25%
Vendor Advisory qnap.com
Affected: QNAP Systems Inc. Q’center
Affected: QNAP Systems Inc. Q’center
Affected: QNAP Systems Inc. Q’center
Affected: QNAP Systems Inc. Q’center
Affected: QNAP Systems Inc. Q’center
Published at:
Updated at:

References

Link Tags
https://www.qnap.com/zh-tw/security-advisory/qsa-21-20 vendor advisory
https://www.shielder.it/advisories/qnap-qcenter-virtual-stored-xss/ third party advisory exploit
https://www.shielder.it/advisories/qnap-qcenter-post-auth-remote-code-execution-via-qpkg/ third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-28807?
CVE-2021-28807 has been scored as a high severity vulnerability.
How to fix CVE-2021-28807?
To fix CVE-2021-28807: 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
Is CVE-2021-28807 being actively exploited in the wild?
It is possible that CVE-2021-28807 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-28807?
CVE-2021-28807 affects QNAP Systems Inc. Q’center, QNAP Systems Inc. Q’center, QNAP Systems Inc. Q’center, QNAP Systems Inc. Q’center, QNAP Systems Inc. Q’center.
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