CVE-2021-38688

Private information access via undisclosed authentication flaw

Published Dec 29, 2021 · Updated Sep 16, 2024

Improper authentication in QNAP Qfile before 3.0.0.1105 for Android allows attackers to compromise the app and access private information. QNAP has not disclosed the affected code locus or the authentication operation that mishandles untrusted input. Exploitation requires attackers to occupy an adjacent network position and induce user interaction; QNAP does not further bound app compromise.

CVSS severity7.1
High
EPSS probability0.81%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in QNAP Qfile before 3.0.0.1105 for Android allows attackers to compromise the app and access private information. QNAP has not disclosed the affected code locus or the authentication operation that mishandles untrusted input. Exploitation requires attackers to occupy an adjacent network position and induce user interaction; QNAP does not further bound app compromise.

The record

CVE
CVE-2021-38688
Published
Dec 29, 2021
Updated
Sep 16, 2024
Vendor
Linn Products Limited
Product
Qfile
Classifications
CWE-287
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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 <3.0.0.1105

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Linn Products Limited · Qfileversion=unspecified <3.0.0.1105

Published CVSS scores

7.1QNAP Systems, Inc.CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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.

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No observations available

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

Weakness, pattern, technique

CWE-287Improper Authentication

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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