CVE-2021-28805

Application-data disclosure via embedded sensitive information

Published Jun 11, 2021 · Updated Sep 17, 2024

Sensitive-information exposure in QNAP QSS allows local users to read application data from affected QSW managed switches. QNAP states that sensitive information is included in the source code but does not identify the file, value, or code path that exposes it. Reachability requires local low-privileged access according to NVD, and the documented consequence is confined to reading application data.

CVSS severity5.5
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive-information exposure in QNAP QSS allows local users to read application data from affected QSW managed switches. QNAP states that sensitive information is included in the source code but does not identify the file, value, or code path that exposes it. Reachability requires local low-privileged access according to NVD, and the documented consequence is confined to reading application data.

The record

CVE
CVE-2021-28805
Published
Jun 11, 2021
Updated
Sep 17, 2024
Vendor
Linn Products Limited
Product
QNAP Switch System
Classifications
CWE-540, CWE-200, T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <1.0.12 build 20210506
  2. Affected versionversion=unspecified <1.0.3 build 20210505

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Linn Products Limited · QNAP Switch Systemversion=unspecified <1.0.12 build 20210506; version=unspecified <1.0.3 build 20210505

Published CVSS scores

2.1NIST NVDAV:L/AC:L/Au:N/C:P/I:N/A:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
7.8QNAP Systems, Inc.CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-540Inclusion of Sensitive Information in Source Code
CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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