QNAP QTS/QuTS hero format string

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in QNAP QTS and QuTS hero. The impacted element is an unknown function. Executing a manipulation can lead to format string. This vulnerability is tracked as CVE-2025-53591. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in QNAP QTS and QuTS hero (the affected version unknown) and classified as problematic. This vulnerability affects an unknown part. The manipulation with an unknown input leads to a format string vulnerability. The CWE definition for the vulnerability is CWE-134. The product uses a function that accepts a format string as an argument, but the format string originates from an external source. As an impact it is known to affect availability. CVE summarizes:

A use of externally-controlled format string vulnerability has been reported to affect several QNAP operating system versions. If a remote attacker gains an administrator account, they can then exploit the vulnerability to obtain secret data or modify memory. We have already fixed the vulnerability in the following versions: QTS 5.2.7.3256 build 20250913 and later QuTS hero h5.2.7.3256 build 20250913 and later QuTS hero h5.3.1.3250 build 20250912 and later

The weakness was disclosed by coral as qsa-25-50. The advisory is shared for download at qnap.com. This vulnerability was named CVE-2025-53591 since 07/04/2025. The exploitation appears to be easy. The attack can be initiated remotely. Additional levels of successful authentication are required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0011). Once again VulDB remains the best source for vulnerability data.

Affected

  • QNAP NAS

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.5

VulDB Base Score: 2.7
VulDB Temp Score: 2.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Format string
CWE: CWE-134 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/04/2025 CVE reserved
01/02/2026 +182 days Advisory disclosed
01/02/2026 +0 days VulDB entry created
01/06/2026 +4 days VulDB entry last update

Sourcesinfo

Vendor: qnap.com

Advisory: qsa-25-50
Researcher: coral
Status: Confirmed

CVE: CVE-2025-53591 (🔒)
GCVE (CVE): GCVE-0-2025-53591
GCVE (VulDB): GCVE-100-339412
CERT Bund: WID-SEC-2026-0011 - QNAP NAS: Mehrere Schwachstellen

Entryinfo

Created: 01/02/2026 16:47
Updated: 01/06/2026 01:57
Changes: 01/02/2026 16:47 (68), 01/03/2026 05:30 (1), 01/05/2026 23:05 (11), 01/06/2026 01:57 (7)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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