QNAP Systems Qsync Central prior 5.0.0.4 out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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7.5$0-$5k0.00

Summaryinfo

A vulnerability was found in QNAP Systems Qsync Central. It has been declared as critical. The impacted element is an unknown function. Executing a manipulation can lead to out-of-bounds write. The identification of this vulnerability is CVE-2025-30276. The attack may be launched remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in QNAP Systems Qsync Central. This vulnerability affects some unknown processing. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect availability. CVE summarizes:

An out-of-bounds write vulnerability has been reported to affect Qsync Central. If a remote attacker gains a user account, they can then exploit the vulnerability to modify or corrupt memory. We have already fixed the vulnerability in the following version: Qsync Central 5.0.0.4 ( 2026/01/20 ) and later

The weakness was shared by coral as qsa-26-02. The advisory is shared for download at qnap.com. This vulnerability was named CVE-2025-30276 since 03/20/2025. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available.

Upgrading to version 5.0.0.4 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

License

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: 7.6
VulDB Meta Temp Score: 7.5

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / 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: 🔒

Upgrade: Qsync Central 5.0.0.4

Timelineinfo

03/20/2025 CVE reserved
02/11/2026 +328 days Advisory disclosed
02/11/2026 +0 days VulDB entry created
02/12/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: qsa-26-02
Researcher: coral
Status: Confirmed

CVE: CVE-2025-30276 (🔒)
GCVE (CVE): GCVE-0-2025-30276
GCVE (VulDB): GCVE-100-345484

Entryinfo

Created: 02/11/2026 14:43
Updated: 02/12/2026 14:22
Changes: 02/11/2026 14:43 (68), 02/12/2026 14:22 (12)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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