CVE-2025-29894 Overview
CVE-2025-29894 is a SQL injection vulnerability [CWE-89] affecting QNAP Qsync Central. An authenticated remote attacker with a valid user account can inject crafted SQL statements to execute unauthorized code or commands on the affected system. QNAP addressed the issue in Qsync Central version 4.5.0.7 released on 2025/04/23. The flaw stems from improper neutralization of user-supplied input in SQL queries, allowing manipulation of database operations and potential command execution within the application context.
Critical Impact
Authenticated attackers can execute unauthorized code or commands on QNAP Network Attached Storage (NAS) devices running vulnerable Qsync Central versions, threatening confidentiality, integrity, and availability of stored data.
Affected Products
- QNAP Qsync Central versions prior to 4.5.0.7
- QNAP NAS devices running affected Qsync Central installations
- Environments exposing Qsync Central to authenticated remote users
Discovery Timeline
- 2025-08-29 - CVE-2025-29894 published to the National Vulnerability Database (NVD)
- 2025-09-19 - Last updated in NVD database
Technical Details for CVE-2025-29894
Vulnerability Analysis
The vulnerability is classified as Improper Neutralization of Special Elements used in an SQL Command [CWE-89]. Qsync Central fails to properly sanitize input before constructing SQL queries. An authenticated remote attacker can supply crafted parameters that alter the intended query logic. Successful exploitation enables execution of unauthorized code or commands within the application context.
The attack proceeds over the network and requires low privileges plus some user interaction, according to the published CVSS 4.0 vector. Because Qsync Central handles file synchronization across QNAP NAS environments, compromise can expose synchronized data and configuration across connected endpoints.
Root Cause
The root cause is improper input validation and the absence of parameterized queries in affected Qsync Central code paths. User-controlled values flow into SQL statements without sufficient neutralization, allowing query manipulation by an authenticated user.
Attack Vector
Exploitation requires an attacker to first obtain a valid Qsync Central user account. With that foothold, the attacker submits requests containing malicious SQL payloads to vulnerable endpoints. The injected SQL is executed by the backend database, enabling unauthorized code or command execution. Refer to the QNAP Security Advisory QSA-25-22 for vendor-confirmed technical details.
No public proof-of-concept exploit is available at the time of publication, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.
Detection Methods for CVE-2025-29894
Indicators of Compromise
- Anomalous authenticated requests to Qsync Central endpoints containing SQL metacharacters such as single quotes, UNION, SELECT, or comment sequences
- Unexpected database errors or stack traces in Qsync Central application logs
- New or unexpected user accounts, scheduled tasks, or processes spawned by the Qsync Central service
- Outbound network connections from the NAS device to unfamiliar hosts following authenticated sessions
Detection Strategies
- Review Qsync Central HTTP access logs for parameter values containing SQL syntax patterns originating from authenticated sessions
- Correlate failed and successful authentication events with subsequent abnormal query patterns or response sizes
- Inspect QNAP NAS system logs for unexpected command execution or privilege changes coinciding with Qsync Central activity
Monitoring Recommendations
- Forward QNAP NAS and Qsync Central logs to a centralized logging or SIEM platform for retention and correlation
- Alert on authentication anomalies such as logins from new geographies, brute-force attempts, or credential reuse against Qsync Central
- Track installed Qsync Central versions across the fleet and alert when devices remain below 4.5.0.7
How to Mitigate CVE-2025-29894
Immediate Actions Required
- Upgrade Qsync Central to version 4.5.0.7 (released 2025/04/23) or later on all QNAP NAS devices
- Audit Qsync Central user accounts and remove unused or unnecessary accounts
- Enforce strong, unique passwords and enable two-factor authentication for all Qsync Central users
- Restrict network exposure of Qsync Central management interfaces to trusted networks or VPN access only
Patch Information
QNAP fixed the vulnerability in Qsync Central 4.5.0.7 and later. Patch details and download instructions are available in the QNAP Security Advisory QSA-25-22. Administrators should apply the update through the QNAP App Center on each affected NAS device.
Workarounds
- Disable Qsync Central on affected NAS devices until the update can be applied
- Limit access to Qsync Central using firewall rules, IP allowlisting, or QNAP's built-in access protection features
- Reduce account privileges so that Qsync Central users hold only the minimum permissions required for their role
# Verify Qsync Central version on a QNAP NAS via SSH
qpkg_cli --list | grep -i "Qsync Central"
# Recommended action: upgrade to 4.5.0.7 or later through the App Center
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
