CVE-2025-53590
📋 TL;DR
A NULL pointer dereference vulnerability in QNAP operating systems allows remote attackers with administrator credentials to cause denial-of-service conditions. This affects QNAP NAS devices running vulnerable QTS versions. The vulnerability requires administrative access to exploit.
💻 Affected Systems
- QNAP NAS devices
⚠️ Risk & Real-World Impact
Worst Case
Complete system crash or reboot, rendering the QNAP device unavailable until manually restarted, potentially causing data access disruption.
Likely Case
Service disruption affecting specific QNAP applications or services, requiring system reboot to restore functionality.
If Mitigated
No impact if proper access controls prevent unauthorized administrative access.
🎯 Exploit Status
Exploitation requires administrative credentials. The vulnerability is a straightforward NULL pointer dereference once authenticated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: QTS 5.2.7.3256 build 20250913 and later
Vendor Advisory: https://www.qnap.com/en/security-advisory/qsa-25-50
Restart Required: Yes
Instructions:
1. Log into QTS web interface as administrator. 2. Go to Control Panel > System > Firmware Update. 3. Check for updates and install QTS 5.2.7.3256 or later. 4. Reboot the NAS when prompted.
🔧 Temporary Workarounds
Restrict administrative access
allLimit administrative account access to trusted IP addresses and networks only.
Configure firewall rules to restrict QTS admin interface access to specific IP ranges
Implement strong authentication
allEnforce strong passwords and enable two-factor authentication for all admin accounts.
Enable 2FA in QTS Control Panel > Security > Two-factor Authentication
🧯 If You Can't Patch
- Isolate QNAP devices from untrusted networks and internet exposure
- Implement strict access controls and monitor for unauthorized admin login attempts
🔍 How to Verify
Check if Vulnerable:
Check QTS version in Control Panel > System > Firmware Update. If version is earlier than 5.2.7.3256 build 20250913, the system is vulnerable.Check Version:
ssh admin@qnap-ip 'cat /etc/config/uLinux.conf | grep version'Verify Fix Applied:
Confirm QTS version shows 5.2.7.3256 or later in Control Panel > System > Firmware Update.📡 Detection & Monitoring
Log Indicators:
- Multiple failed admin login attempts followed by system crash/reboot logs
- Unexpected system reboots in /var/log/messages
Network Indicators:
- Multiple authentication attempts to QTS admin interface from unusual sources
- Sudden loss of connectivity to QNAP services
SIEM Query:
source="qnap" AND (event_type="authentication_failure" OR event_type="system_reboot")