CVE-2021-38682Network attack vector

Unauthenticated code execution via stack buffer overflow

Published Jan 14, 2022 · Updated Sep 16, 2024

Stack buffer overflow in QNAP QVR Elite, QVR Pro, and QVR Guard allows remote attackers to execute arbitrary code over the network. QNAP has not disclosed the affected function, the input that reaches the stack buffer, or the unchecked copy operation. No authentication or user interaction is required, but successful exploitation depends on unspecified environmental conditions.

CVSS severity8.1
High
EPSS probability1.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack buffer overflow in QNAP QVR Elite, QVR Pro, and QVR Guard allows remote attackers to execute arbitrary code over the network. QNAP has not disclosed the affected function, the input that reaches the stack buffer, or the unchecked copy operation. No authentication or user interaction is required, but successful exploitation depends on unspecified environmental conditions.

The record

CVE
CVE-2021-38682
Published
Jan 14, 2022
Updated
Sep 16, 2024
Vendor
Linn Products Limited
Product
QVR Guard
Classifications
CWE-787, CWE-120, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 14, 2022CVE 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 <2.1.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Linn Products Limited · QVR Guardversion=unspecified <2.1.3.0
Linn Products Limited · QVR Eliteversion=unspecified <2.1.4.0 (2021/12/06)
Linn Products Limited · QVR Proversion=unspecified <2.1.3.0 (2021/12/06)

Published CVSS scores

9.8NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.1QNAP Systems, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1190Exploit Public-Facing Application

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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