CVE-2025-57200: Avtech DGM1104 Firmware RCE Vulnerability

CVE-2025-57200 Overview

CVE-2025-57200 is an authenticated command injection vulnerability affecting the AVTECH SECURITY Corporation DGM1104 device running firmware FullImg-1015-1004-1006-1003. The flaw resides in the test_mail function, where unsanitized user-supplied input flows into a system command context. Authenticated attackers can inject arbitrary operating system commands through crafted parameters. The weakness is classified under [CWE-77] Improper Neutralization of Special Elements used in a Command. Successful exploitation leads to arbitrary command execution on the embedded device with the privileges of the vulnerable process.

Critical Impact

Authenticated attackers can execute arbitrary commands on affected AVTECH DGM1104 devices through crafted input to the test_mail function, enabling unauthorized access to device internals and network pivoting.

Affected Products

• AVTECH SECURITY Corporation DGM1104 (hardware)
• AVTECH DGM1104 Firmware FullImg-1015-1004-1006-1003
• Deployments exposing the device management interface over the network

Discovery Timeline

• 2025-12-03 - CVE-2025-57200 published to the National Vulnerability Database (NVD)
• 2026-07-05 - Last updated in NVD database

Technical Details for CVE-2025-57200

Vulnerability Analysis

The vulnerability is a command injection flaw in the test_mail function of the AVTECH DGM1104 web management interface. The function is designed to validate email notification configuration by triggering a test message. It accepts user-controlled parameters and passes them into a shell command context without proper neutralization of shell metacharacters.

Exploitation requires prior authentication to the device. Once authenticated, an attacker submits a crafted request containing shell metacharacters such as backticks, semicolons, or command substitution syntax. The injected commands execute in the context of the web management process on the embedded Linux system. This allows arbitrary command execution, configuration modification, credential extraction, and pivoting into internal networks.

Root Cause

The root cause is improper neutralization of special elements used in an OS command [CWE-77]. The test_mail handler concatenates attacker-controlled input into a command string executed by a shell interpreter. No allow-list validation, escaping, or safe command execution API is used to isolate arguments from the command syntax.

Attack Vector

The attack vector is network-based and requires valid credentials on the DGM1104 management interface. An attacker sends an HTTP request to the test_mail endpoint with a payload embedded in a vulnerable parameter. The device's backend passes the payload to a shell, executing the attacker's commands alongside the intended mail test operation. Because the vulnerability affects an internet-facing embedded appliance, compromised or default credentials materially increase risk.

No verified exploit code is published in the NVD entry. Technical details are available in the GitHub PoC Repository.

Detection Methods for CVE-2025-57200

Indicators of Compromise

• Unexpected outbound connections initiated by the DGM1104 device following authenticated sessions to the management interface
• HTTP POST requests to the test_mail endpoint containing shell metacharacters such as ;, |, &&, `, or $(
• Unusual child processes spawned by the device web server, particularly sh, wget, curl, nc, or busybox invocations
• Modifications to device configuration files or credential stores immediately after mail test operations

Detection Strategies

• Inspect web server and management interface access logs for test_mail requests containing suspicious characters or long parameter values
• Deploy network intrusion detection signatures for command injection payloads targeting AVTECH management endpoints
• Baseline normal outbound traffic from CCTV and DVR appliances and alert on deviations

Monitoring Recommendations

• Forward device syslog and authentication events to a centralized logging platform for correlation
• Monitor authentication attempts against DGM1104 devices and alert on brute-force or credential-stuffing patterns
• Track firmware version inventory to identify hosts running FullImg-1015-1004-1006-1003

How to Mitigate CVE-2025-57200

Immediate Actions Required

• Restrict management interface access to trusted administrative networks using firewall access control lists or VLAN segmentation
• Rotate all administrator credentials on affected DGM1104 devices and enforce strong, unique passwords
• Audit device access logs for prior use of the test_mail endpoint with suspicious payloads
• Review outbound connection logs from DGM1104 devices for signs of post-exploitation activity

Patch Information

As of the last NVD update on 2026-07-05, no vendor advisory or patched firmware release is referenced for CVE-2025-57200. Administrators should monitor the AVTECH support channels for firmware updates addressing the test_mail command injection and apply them once available. Refer to the GitHub PoC Repository for technical context.

Workarounds

• Place affected devices behind a VPN and prohibit direct exposure of the management interface to the internet
• Disable or block access to the mail test functionality at the network layer where feasible
• Apply the principle of least privilege by restricting management accounts to specific administrator source addresses
• Consider decommissioning end-of-life or unpatched appliances and replacing them with supported hardware

# Example firewall restriction limiting management access to a trusted subnet
iptables -A INPUT -p tcp --dport 80 -s 10.10.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -s 10.10.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP