CVE-2021-28803
Stored XSS Vulnerability in Q'center
This issue affects: QNAP Systems Inc. Q'center versions prior to 1.11.1004.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
This issue affects: QNAP Systems Inc. Q'center versions prior to 1.11.1004.
- Record
CVE-2021-28803- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:N/I:P/A:N - Weakness
- CWE-80, CWE-79
- Updated
- 2026-11-02
CVE List No score
Stored XSS Vulnerability in Q'center
This issue affects: QNAP Systems Inc. Q'center versions prior to 1.11.1004.
- Record
CVE-2021-28803- Weakness
- CWE-80
- Updated
- 2026-11-02
EUVDEUVD-2021-15459 No score
This issue affects: QNAP Systems Inc. Q'center versions prior to 1.11.1004.
- Record
EUVD-2021-15459- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-5g7h-5qvh-cr9r No score
This issue affects: QNAP Systems Inc. Q'center versions prior to 1.11.1004.
This issue affects: QNAP Systems Inc. Q'center versions prior to 1.11.1004.
- Record
GHSA-5g7h-5qvh-cr9r- Weakness
- CWE-79, CWE-80
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-28803 is a medium vulnerability (CVSS 5.4) in Qnap Systems Inc. Q'center, published July 1, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.47%, the 40th percentile. No source names a fixed version.