CVE-2021-28801

mediumpriority · track · 30EPSS 0.007 · 55 %ileEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.75% (55th) EPSS
CVSS 5 · medium
Is it mine?
2 products
Check your exposure
Who says so?
3 sources
cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 3.1–7.5

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.13.1lowCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:Nsecondary · ENISA EU
v3.13.1lowCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:Nsecondary · security@qnapsecurity.com.twexploitability 1.6 · impact 1.4
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125US
03

affected products (2)

Products and version ranges known to be affected.

04

also known as (3)

Other names and identifiers for this entity.

05

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdNVDCVE.orgMITRE
published 2021-06-11modified 2026-06-17
06

references (4)

External citations — patches, advisories, analysis.

scry

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