CVE-2026-73167 Overview
CVE-2026-73167 is an OS command injection vulnerability affecting the web management interface of the Advantech EKI-1242IEIMS industrial protocol gateway running firmware version V1.06.01. Nozomi Networks Labs identified the flaw, which is classified under CWE-78: Improper Neutralization of Special Elements used in an OS Command. A remote authenticated attacker can inject crafted parameters into HTTP requests and execute arbitrary operating system commands as root. Successful exploitation grants full control over the device, exposing the industrial network segment it bridges.
Critical Impact
Authenticated attackers can execute arbitrary OS commands as root on affected Advantech EKI-1242IEIMS gateways, resulting in complete device compromise and pivot opportunities into operational technology environments.
Affected Products
- Advantech EKI-1242IEIMS industrial protocol gateway
- Firmware version V1.06.01
- Web management interface component
Discovery Timeline
- 2026-09-16 - CVE-2026-73167 published to the National Vulnerability Database
- 2026-09-16 - Last updated in NVD database
Technical Details for CVE-2026-73167
Vulnerability Analysis
The Advantech EKI-1242IEIMS exposes a web-based management interface that processes user-supplied request parameters and passes them to underlying operating system utilities. The interface fails to neutralize shell metacharacters before constructing command strings executed by the device's shell. An authenticated attacker with access to the management interface can append arbitrary commands to legitimate parameter values and have them executed by the root account.
Because the gateway sits between IT networks and industrial serial or fieldbus devices, code execution on the appliance allows adversaries to manipulate protocol translations, capture engineering traffic, and pivot deeper into operational technology (OT) environments. The vulnerability requires network reachability to the web interface and valid credentials, but privilege requirements are the only meaningful barrier since exploitation is deterministic once access is obtained.
Root Cause
The root cause is missing input sanitization in the request handlers of the web management interface. Parameter values received from authenticated HTTP requests are concatenated directly into OS command strings without escaping, quoting, or allowlist validation. This constitutes CWE-78, OS Command Injection.
Attack Vector
The attack originates from the network. An attacker with valid management credentials submits a crafted HTTP request containing shell metacharacters such as ;, |, or ` within a vulnerable parameter. The web application invokes a shell to run the composed command, and the injected payload executes with root privileges. Compromised or default credentials on internet-exposed devices materially lower the barrier to exploitation.
No verified public proof-of-concept code is available. Technical specifics are described in the Nozomi Networks CVE-2026-73167 Advisory and the Advantech Security Advisory EKI-1242IEIMS.
Detection Methods for CVE-2026-73167
Indicators of Compromise
- Unexpected outbound connections initiated by the EKI-1242IEIMS management IP address, particularly to attacker-controlled infrastructure or non-industrial destinations.
- Web server access log entries containing shell metacharacters such as ;, |, &, $(, or backticks in query strings or POST bodies targeting the management interface.
- New or modified files in writable filesystem paths on the gateway, or unexpected processes spawned by the web server parent process.
Detection Strategies
- Deploy network intrusion detection signatures that inspect HTTP requests to the EKI-1242IEIMS management interface for shell metacharacter payloads in parameters.
- Baseline normal administrative traffic to the device and alert on request patterns, user agents, or source addresses that deviate from that baseline.
- Correlate authentication events on the gateway with subsequent command executions or configuration changes to identify credential abuse.
Monitoring Recommendations
- Forward web management interface logs and syslog output from the gateway to a centralized SIEM or data lake for retention and analysis.
- Monitor OT network segments for lateral movement originating from protocol gateways, including unexpected scanning or protocol traffic.
- Track firmware version and configuration integrity across all deployed EKI-1242IEIMS units to detect unauthorized changes.
How to Mitigate CVE-2026-73167
Immediate Actions Required
- Restrict network access to the EKI-1242IEIMS web management interface to a dedicated management VLAN reachable only from authorized administrator workstations.
- Rotate all administrative credentials on affected devices and disable any default or shared accounts.
- Audit web server access logs for suspicious parameter content and investigate any anomalous command execution or outbound connections.
Patch Information
Advantech has published guidance for this vulnerability in the Advantech Security Advisory EKI-1242IEIMS. Operators running firmware V1.06.01 should review the advisory and apply the vendor-recommended firmware update or configuration changes on all affected units. Additional technical detail is available in the Nozomi Networks CVE-2026-73167 Advisory.
Workarounds
- Place affected gateways behind a firewall that blocks all inbound access to the management interface except from a hardened jump host.
- Disable the web management interface where practical and administer devices through out-of-band or serial console access.
- Enforce strong, unique credentials and multi-factor authentication on any upstream systems that reach the management network.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.