CVE-2021-28801
Out-of-Bounds Read Vulnerability in QSS
- Published
- Updated
- Reserved
- Assigned by
- qnap
Description
An out-of-bounds read vulnerability has been reported to affect certain QNAP switches running QSS. If exploited, this vulnerability allows attackers to read sensitive information on the system. This issue affects: QNAP Systems Inc. QSS versions prior to 1.0.2 build 20210122 on QSW-M2108-2C; versions prior to 1.0.2 build 20210122 on QSW-M2108-2S; versions prior to 1.0.2 build 20210122 on QSW-M2108R-2C.
Timeline
ID reserved
By qnap
- 3 months later
· 3 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| qnapCNA (assigner) | 3.1 | Low3.1 | CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.75% · top 45% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.1.
Weakness
Affected products
- affected unspecified – < 1.0.2 build 20210122
- affected unspecified – < 1.0.2 build 20210122
- affected unspecified – < 1.0.2 build 20210122
What to do
Solution: QNAP have already fixed this vulnerability in the following versions: QSW-M2108-2C: QSS 1.0.2 build 20210122 and later QSW-M2108-2S: QSS 1.0.2 build 20210122 and later QSW-M2108R-2C: QSS 1.0.2 build 20210122 and later
References (1)
- https://www.qnap.com/zh-tw/security-advisory/qsa-21-23 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-28801)Record last updated .