CVE-2025-30264: QNAP QTS Command Injection Vulnerability

CVE-2025-30264 Overview

CVE-2025-30264 is a command injection vulnerability [CWE-77] affecting multiple versions of QNAP QTS and QuTS hero operating systems. An authenticated remote attacker who obtains a valid user account can exploit the flaw to execute arbitrary commands on the underlying NAS device. QNAP addressed the issue in QTS 5.2.5.3145 build 20250526 and QuTS hero h5.2.5.3138 build 20250519. The vulnerability was published to the National Vulnerability Database on August 29, 2025, with a CVSS 4.0 score of 7.7.

Critical Impact
Authenticated attackers can inject arbitrary operating system commands on QNAP NAS devices, leading to full compromise of stored data and the appliance itself.

Affected Products

QNAP QTS versions prior to 5.2.5.3145 build 20250526
QNAP QuTS hero versions prior to h5.2.5.3138 build 20250519
QTS 5.2.0.x through 5.2.4.x build branches as listed in CPE inventory

Discovery Timeline

2025-08-29 - CVE-2025-30264 published to NVD
2025-09-22 - Last updated in NVD database

Technical Details for CVE-2025-30264

Vulnerability Analysis

The flaw is a command injection issue categorized under [CWE-77], Improper Neutralization of Special Elements used in a Command. QNAP QTS and QuTS hero accept user-supplied input that is passed into a command interpreter without sufficient sanitization. An authenticated remote attacker can append shell metacharacters to manipulate the constructed command and execute arbitrary operating system instructions in the context of the vulnerable service.

Successful exploitation impacts confidentiality, integrity, and availability of the NAS device. Attackers can read or modify stored data, deploy persistence mechanisms, pivot into adjacent network segments, or stage ransomware. The EPSS probability is 0.339%, indicating low observed exploitation activity at the time of publication.

Root Cause

The vulnerability stems from improper neutralization of special elements within input passed to a command shell. The affected component constructs system commands using attacker-controlled strings, allowing metacharacters such as ;, |, &, and backticks to break out of the intended command context. QNAP has not publicly disclosed the specific binary or function affected beyond the advisory QSA-25-21.

Attack Vector

Exploitation requires network access to the QNAP management interface and a valid user account on the device. Once authenticated, the attacker submits a crafted request to the vulnerable endpoint with injected shell payloads. Because QTS services typically run with elevated privileges, command execution can quickly escalate to full device compromise.

No public proof-of-concept exploit is available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. Technical specifics of the injection sink are described in the QNAP Security Advisory QSA-25-21.

Detection Methods for CVE-2025-30264

Indicators of Compromise

Unexpected child processes spawned by QTS or QuTS hero web-facing daemons, particularly /bin/sh, wget, curl, or busybox invocations
Authenticated sessions originating from unusual IP addresses followed by abnormal command-line activity on the NAS
New cron entries, modified authorized_keys files, or unfamiliar binaries written to /share/ or /tmp/
Outbound connections from the NAS to unknown command-and-control infrastructure

Detection Strategies

Inspect QNAP system logs (/var/log/) and the QuLog Center for failed authentication followed by successful logins and command execution events
Monitor for process lineage anomalies where HTTP or API daemons spawn shell interpreters
Hunt for shell metacharacters such as ;, &&, ||, $(, or backticks inside HTTP request bodies and URL parameters targeting QNAP management endpoints
Correlate authentication telemetry with subsequent file system modifications to detect post-exploitation activity

Monitoring Recommendations

Forward QNAP syslog, QuLog Center, and network telemetry to a centralized SIEM for retention and correlation
Enable QuFirewall and review allow-listed administrative source IPs on a recurring basis
Alert on creation of new local users, SSH key changes, or modifications to startup scripts on QNAP devices
Track outbound connections from NAS appliances and baseline expected destinations

How to Mitigate CVE-2025-30264

Immediate Actions Required

Upgrade QTS to 5.2.5.3145 build 20250526 or later, and QuTS hero to h5.2.5.3138 build 20250519 or later
Audit all local user accounts on affected devices and remove unused or stale accounts
Rotate passwords for all NAS users and enforce strong password policies with two-factor authentication
Restrict management interface access to trusted internal networks and disable direct exposure to the internet

Patch Information

QNAP released fixed versions on May 19, 2025 (QuTS hero) and May 26, 2025 (QTS). Customers should apply updates through the QTS Control Panel under Firmware Update, or download installers directly from the QNAP support portal. Refer to QNAP Security Advisory QSA-25-21 for vendor guidance and complete version mappings.

Workarounds

Disable remote access to the QNAP web administration interface until the firmware update is applied
Place the NAS behind a VPN and require multi-factor authentication for all administrative sessions
Use QuFirewall to restrict source IP ranges that can authenticate to the management UI
Limit user account privileges to the minimum required and revoke administrator rights from non-essential accounts

bash

# Configuration example - restricting administrative access via QuFirewall
# Allow only the corporate management subnet to reach the QTS web UI
qufirewall rule add --action allow --src 10.10.50.0/24 --dst-port 443 --proto tcp
qufirewall rule add --action deny --src 0.0.0.0/0 --dst-port 443 --proto tcp
qufirewall enable