CVE-2025-29893 Overview
CVE-2025-29893 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 through vulnerable input parameters. Successful exploitation allows execution of unauthorized code or commands on the affected system.
QNAP addressed the issue in Qsync Central version 4.5.0.7 released on April 23, 2025. The vulnerability requires low privileges and user interaction, but it impacts the confidentiality, integrity, and availability of affected installations. Administrators running earlier versions should upgrade immediately.
Critical Impact
Authenticated attackers can execute unauthorized code or commands on Qsync Central servers through SQL injection, compromising file synchronization infrastructure.
Affected Products
- QNAP Qsync Central versions prior to 4.5.0.7
- QNAP NAS devices running vulnerable Qsync Central installations
- Centralized file synchronization deployments using Qsync Central
Discovery Timeline
- 2025-04-23 - QNAP releases Qsync Central 4.5.0.7 with the security fix
- 2025-08-29 - CVE-2025-29893 published to NVD
- 2025-09-19 - Last updated in NVD database
Technical Details for CVE-2025-29893
Vulnerability Analysis
The flaw is a SQL injection vulnerability [CWE-89] in QNAP Qsync Central, a centralized file synchronization application for QNAP NAS devices. Qsync Central manages user accounts, synchronization rules, and file metadata through backend database queries.
The vulnerability stems from insufficient sanitization of user-supplied input before that input reaches SQL query construction. An authenticated attacker can supply crafted parameters that alter the intended query logic. The advisory states this can lead to execution of unauthorized code or commands, indicating the SQL injection can be leveraged beyond simple data exfiltration.
Exploitation requires a valid user account, which limits unauthenticated mass exploitation but does not prevent attacks from insiders, compromised accounts, or attackers who obtain credentials through phishing or credential stuffing.
Root Cause
The root cause is improper neutralization of special elements used in an SQL command. Qsync Central does not consistently apply parameterized queries or input validation to user-controlled fields before incorporating them into database statements. This allows an attacker to break out of the intended query context and append arbitrary SQL.
Attack Vector
The attack vector is network-based and requires authentication. An attacker with valid Qsync Central credentials sends crafted requests to a vulnerable endpoint. The malicious payload injects SQL syntax that the backend executes against the application database. According to the QNAP advisory, the resulting impact can extend to unauthorized code or command execution on the host.
No public proof-of-concept exploit is currently available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. Refer to the QNAP Security Advisory QSA-25-22 for vendor details.
Detection Methods for CVE-2025-29893
Indicators of Compromise
- Unexpected database queries containing SQL meta-characters such as single quotes, UNION, SELECT, or comment sequences in Qsync Central application logs
- Anomalous authenticated sessions originating from unusual geolocations or IP ranges
- New or modified files in Qsync Central directories outside scheduled synchronization windows
- Unexpected processes spawned by the Qsync Central service account on the NAS
Detection Strategies
- Inspect Qsync Central HTTP request logs for parameters containing SQL syntax patterns or encoded equivalents
- Monitor database error responses and lengthy or malformed query patterns in application logs
- Correlate authentication events with subsequent administrative or database-related activity on the NAS
Monitoring Recommendations
- Enable verbose logging on Qsync Central and forward logs to a centralized SIEM for analysis
- Track outbound connections from the NAS that deviate from baseline synchronization traffic
- Audit user accounts on Qsync Central for unused or stale credentials that could be abused by an attacker
How to Mitigate CVE-2025-29893
Immediate Actions Required
- Upgrade Qsync Central to version 4.5.0.7 (released April 23, 2025) or later through the QNAP App Center
- Audit all Qsync Central user accounts and remove or disable accounts that are no longer required
- Reset credentials for accounts with elevated privileges and enforce strong password policies
- Restrict network access to Qsync Central management interfaces to trusted administrative networks
Patch Information
QNAP fixed the vulnerability in Qsync Central 4.5.0.7, released on April 23, 2025. Administrators should install the update via the QNAP App Center on each affected NAS. Full details are available in the QNAP Security Advisory QSA-25-22.
Workarounds
- Limit Qsync Central exposure to the internet by placing the NAS behind a VPN or firewall
- Enforce multi-factor authentication on all NAS user accounts to reduce risk from compromised credentials
- Apply principle of least privilege so Qsync Central users hold only the permissions required for their role
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
