CVE-2025-52431Network attack vector

Administrator-triggered denial of service via NULL dereference

Published Jan 2, 2026 · Updated Jan 2, 2026

NULL pointer dereference in QNAP QTS 5.2.x and QuTS hero h5.2.x and h5.3.x allows remote authenticated users to cause denial of service. QNAP has not disclosed the affected component, request path, or operation that dereferences the NULL pointer. Administrator privileges are required; successful exploitation interrupts availability without reported data exposure or modification.

CVSS severity4.9
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in QNAP QTS 5.2.x and QuTS hero h5.2.x and h5.3.x allows remote authenticated users to cause denial of service. QNAP has not disclosed the affected component, request path, or operation that dereferences the NULL pointer. Administrator privileges are required; successful exploitation interrupts availability without reported data exposure or modification.

The record

CVE
CVE-2025-52431
Published
Jan 2, 2026
Updated
Jan 2, 2026
Vendor
Linn Products Limited
Product
QuTS hero
Classifications
CWE-476, T1499.004
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jan 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 2, 2026Record 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=h5.2.x <h5.2.7.3256 build 20250913
  2. Affected versionversion=h5.3.x <h5.3.1.3250 build 20250912

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Linn Products Limited · QuTS heroversion=h5.2.x <h5.2.7.3256 build 20250913; version=h5.3.x <h5.3.1.3250 build 20250912
Linn Products Limited · QTSversion=5.2.x <5.2.7.3256 build 20250913

Published CVSS scores

4.9NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
1.2QNAP Systems, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Endpoint Denial of Service: Application or System Exploitation

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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