CVE-2025-57708
📋 TL;DR
This vulnerability in Qsync Central allows authenticated remote attackers to perform resource exhaustion attacks by allocating resources without limits. Attackers with valid user accounts can consume system resources, potentially causing denial-of-service conditions. Organizations using vulnerable versions of Qsync Central are affected.
💻 Affected Systems
- Qsync Central
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete denial-of-service affecting all Qsync Central functionality, potentially disrupting file synchronization services across the organization.
Likely Case
Degraded performance or temporary service interruptions for legitimate users attempting to access Qsync Central resources.
If Mitigated
Minimal impact with proper resource monitoring and rate limiting in place.
🎯 Exploit Status
Exploitation requires valid user credentials but the attack itself is straightforward once authenticated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Qsync Central 5.0.0.4 (2026/01/20) and later
Vendor Advisory: https://www.qnap.com/en/security-advisory/qsa-26-02
Restart Required: Yes
Instructions:
1. Log into QNAP App Center. 2. Check for updates to Qsync Central. 3. Install version 5.0.0.4 or later. 4. Restart Qsync Central service or the entire NAS if required.
🔧 Temporary Workarounds
Implement rate limiting
allConfigure network-level rate limiting for Qsync Central traffic to prevent resource exhaustion
Restrict user access
allLimit Qsync Central access to only necessary users and implement strong authentication controls
🧯 If You Can't Patch
- Implement strict user account management and monitoring for suspicious resource consumption patterns
- Deploy network monitoring and intrusion detection systems to alert on abnormal resource usage
🔍 How to Verify
Check if Vulnerable:
Check Qsync Central version in QNAP App Center or via SSH: cat /etc/config/uLinux.conf | grep qsyncCheck Version:
ssh admin@qnap-nas 'cat /etc/config/uLinux.conf | grep -i qsync'Verify Fix Applied:
Verify Qsync Central version is 5.0.0.4 or later and monitor for resource exhaustion attempts📡 Detection & Monitoring
Log Indicators:
- Unusually high resource consumption logs
- Multiple authentication attempts from single user
- System resource threshold alerts
Network Indicators:
- Abnormal traffic patterns to Qsync Central ports
- Sustained high-volume connections from single IP
SIEM Query:
source="qnap-logs" AND ("resource exhaustion" OR "high memory" OR "high cpu") AND process="qsync"