CVE-2025-30274 Overview
CVE-2025-30274 is a NULL pointer dereference vulnerability [CWE-476] affecting multiple versions of QNAP QTS and QuTS hero operating systems. An authenticated attacker with high privileges can trigger the flaw over the network to cause a denial-of-service (DoS) condition on the affected NAS appliance. QNAP addressed the issue in QTS 5.2.5.3145 build 20250526 and QuTS hero h5.2.5.3138 build 20250519. The vulnerability does not impact confidentiality or integrity, and its scope is limited to availability of the affected service.
Critical Impact
Authenticated remote attackers can crash QNAP NAS services, disrupting file storage and backup operations for connected users and workloads.
Affected Products
- QNAP QTS versions from 5.2.0.2737 build 20240417 through 5.2.4.3092 build 20250403
- QNAP QuTS hero versions from h5.2.0.2737 build 20240417 through h5.2.4.3079 build 20250321
- QNAP NAS appliances running the affected QTS and QuTS hero builds
Discovery Timeline
- 2025-08-29 - CVE-2025-30274 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-30274
Vulnerability Analysis
The vulnerability is a NULL pointer dereference in the QTS and QuTS hero operating systems. When the vulnerable code path executes, it dereferences a pointer that was never initialized or has been set to NULL. This triggers a memory access fault that terminates the affected process. The attacker must already possess high privileges on the system and reach the vulnerable component over the network. Successful exploitation degrades availability of the targeted service without leaking data or modifying stored content.
Root Cause
The root cause is a missing NULL check before pointer dereference, classified under [CWE-476]. The affected code assumes an object or handle is valid without validating it after allocation, lookup, or return from an upstream function. When that assumption fails, the process crashes rather than handling the error gracefully. Improper input validation and insufficient defensive checks in the request-handling path allow an authenticated user to reach the fault reliably.
Attack Vector
Exploitation requires network access to the QNAP management interface and valid credentials with elevated privileges. The attacker sends a crafted request that steers execution into the flawed code path. No user interaction is required beyond the attacker's own authenticated session. The result is a service crash and denial-of-service condition. Because the required privilege level is high, casual or unauthenticated internet exposure is not directly exploitable, though credential theft or insider misuse remains a realistic path.
No public proof-of-concept code, exploit, or CISA KEV listing is currently associated with CVE-2025-30274. Refer to the QNAP Security Advisory QSA-25-21 for vendor-authoritative details.
Detection Methods for CVE-2025-30274
Indicators of Compromise
- Unexpected termination or restart of QTS/QuTS hero services correlated with authenticated administrative sessions.
- Kernel or userland crash logs referencing NULL pointer dereferences on the NAS appliance.
- Repeated failed or malformed API requests from a privileged account preceding a service outage.
Detection Strategies
- Monitor QNAP system logs and syslog for abnormal service restarts, watchdog resets, or process crash entries.
- Correlate administrative authentication events with subsequent availability degradation across storage shares.
- Alert on privileged account activity originating from unexpected IP addresses or geographic locations.
Monitoring Recommendations
- Ingest NAS audit and access logs into a centralized SIEM for retention and behavioral analysis.
- Track uptime and process health metrics on QNAP appliances to identify repeat DoS attempts.
- Enable alerting on administrative logins outside of documented maintenance windows.
How to Mitigate CVE-2025-30274
Immediate Actions Required
- Upgrade affected devices to QTS 5.2.5.3145 build 20250526 or later, or QuTS hero h5.2.5.3138 build 20250519 or later.
- Audit administrative accounts and rotate credentials for any account with elevated privileges on the NAS.
- Restrict management interface exposure to trusted management networks and remove any direct internet exposure.
Patch Information
QNAP has resolved CVE-2025-30274 in QTS 5.2.5.3145 build 20250526 and QuTS hero h5.2.5.3138 build 20250519. Administrators should apply the update through the QTS Control Panel under Firmware Update or via the QNAP download portal. Full details are available in the QNAP Security Advisory QSA-25-21.
Workarounds
- Enforce multi-factor authentication on all administrator accounts to reduce risk of credential-based abuse.
- Place the NAS management interface behind a VPN or restricted management VLAN.
- Apply the principle of least privilege and remove unused administrative accounts.
- Enable QNAP's built-in account access protection to throttle abusive session activity.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.