CVE-2025-66273Network attack vector

Administrator command execution via unsanitized username

Published Jun 10, 2026 · Updated Jun 10, 2026

Command injection in QNAP QTS and QuTS hero allows remote authenticated users with administrator access to execute commands on the NAS. The vulnerable processing path fails to neutralize shell syntax in the username parameter before invoking a system command. Network access to the management interface and an administrator account are required; successful exploitation runs arbitrary commands on the appliance.

CVSS severity8.6
High
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in QNAP QTS and QuTS hero allows remote authenticated users with administrator access to execute commands on the NAS. The vulnerable processing path fails to neutralize shell syntax in the username parameter before invoking a system command. Network access to the management interface and an administrator account are required; successful exploitation runs arbitrary commands on the appliance.

The record

CVE
CVE-2025-66273
Published
Jun 10, 2026
Updated
Jun 10, 2026
Vendor
Linn Products Limited
Product
QuTS hero
Classifications
CWE-78, T1059
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jun 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=h5.2.0 <h5.2.9.3410 build 20260214
  2. Affected versionversion=h5.3.0 <h5.3.4.3500 build 20260520
  3. Affected versionversion=? <h6.0.0.3397 build 20260206

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Linn Products Limited · QuTS heroversion=h5.2.0 <h5.2.9.3410 build 20260214; version=h5.3.0 <h5.3.4.3500 build 20260520; version=? <h6.0.0.3397 build 20260206
Linn Products Limited · QTSversion=5.2.0 <5.2.9.3410 build 20260214

Published CVSS scores

7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
8.6QNAP Systems, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA: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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

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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