QNAP Systems Qsync Central prior 5.0.0.4 buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in QNAP Systems Qsync Central. This issue affects some unknown processing. The manipulation results in buffer overflow. This vulnerability is reported as CVE-2025-52870. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in QNAP Systems Qsync Central. Affected is an unknown function. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on availability. CVE summarizes:

A buffer overflow vulnerability has been reported to affect Qsync Central. If a remote attacker gains a user account, they can then exploit the vulnerability to modify memory or crash processes. We have already fixed the vulnerability in the following version: Qsync Central 5.0.0.4 ( 2026/01/20 ) and later

The weakness was disclosed by Searat and Izut as qsa-26-02. The advisory is shared for download at qnap.com. This vulnerability is traded as CVE-2025-52870 since 06/20/2025. The exploitability is told to be easy. It is possible to launch the attack 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: 6.2
VulDB Meta Temp Score: 6.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.1
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / 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

06/20/2025 CVE reserved
02/11/2026 +236 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: Searat, Izut
Status: Confirmed

CVE: CVE-2025-52870 (🔒)
GCVE (CVE): GCVE-0-2025-52870
GCVE (VulDB): GCVE-100-345492

Entryinfo

Created: 02/11/2026 15:00
Updated: 02/12/2026 15:56
Changes: 02/11/2026 15:00 (35), 02/11/2026 15:01 (33), 02/12/2026 14:22 (1), 02/12/2026 15:56 (11)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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