CVE-2026-78037: Xiiaozet LK100W RCE Vulnerability

CVE-2026-78037 Overview

CVE-2026-78037 is an operating system command injection vulnerability [CWE-78] affecting the Xiiaozet LK100W device. The flaw resides in the web-based management interface and allows an authenticated attacker to execute arbitrary OS commands with elevated privileges. Successful exploitation can lead to unauthorized access to sensitive information or complete device compromise. The vulnerability is remotely exploitable over the network with low attack complexity and requires only low-level authenticated access. CISA published an Industrial Control Systems advisory tracking this issue as ICSA-26-239-01.

Critical Impact
An authenticated attacker on the network can inject OS commands through the LK100W web management interface and gain elevated privileges, resulting in full device compromise.

Affected Products

Xiiaozet LK100W (all versions covered by advisory ICSA-26-239-01)
Deployments exposing the LK100W web-based management interface to reachable networks
Industrial and operational technology environments using the LK100W

Discovery Timeline

2026-08-28 - CVE-2026-78037 published to NVD
2026-08-31 - Last updated in NVD database

Technical Details for CVE-2026-78037

Vulnerability Analysis

The LK100W web-based management interface fails to properly neutralize special elements passed into an OS command. An authenticated user with low privileges can inject shell metacharacters into a vulnerable request parameter, causing the underlying operating system to execute attacker-controlled commands. Because the web service on embedded devices commonly runs as root or an equivalent elevated account, injected commands inherit those privileges. The result is a direct path from authenticated web access to full device takeover, including arbitrary file read/write, configuration tampering, and pivoting into the connected OT network.

Root Cause

The root cause is improper neutralization of special elements used in an OS command [CWE-78]. User-supplied input from the web management interface is concatenated into a shell command string and passed to a system-level execution primitive without sanitization or use of parameterized APIs. Shell metacharacters such as ;, |, &, and backticks are not filtered, enabling command chaining.

Attack Vector

Exploitation requires network reachability to the LK100W web management interface and valid low-privilege credentials. An attacker authenticates to the interface, then submits a crafted request in which a parameter carries shell metacharacters followed by attacker commands. The web backend executes the combined string through a shell, running the injected payload with the privileges of the web service process. No user interaction is required beyond the attacker's own session.

No verified public exploit code is available. Refer to the CISA ICS Advisory ICSA-26-239-01 and the corresponding GitHub CSAF Document for technical details.

Detection Methods for CVE-2026-78037

Indicators of Compromise

Unexpected child processes (for example sh, busybox, wget, curl, nc) spawned by the LK100W web server process.
HTTP requests to the management interface containing shell metacharacters such as ;, |, &&, $(, or backticks in parameter values.
Outbound connections from the LK100W to unfamiliar IP addresses shortly after authenticated management sessions.
New or modified files in web-writable paths, or unexpected changes to device configuration files.

Detection Strategies

Inspect web server access logs on the LK100W for authenticated POST/GET requests containing encoded or literal shell metacharacters.
Correlate authentication events on the management interface with subsequent process execution telemetry from the device or upstream network sensors.
Deploy network intrusion detection signatures that flag command injection patterns targeting embedded device management endpoints.

Monitoring Recommendations

Forward device and network logs to a centralized SIEM or data lake and alert on management-interface authentications from non-administrative source ranges.
Baseline normal command-line activity on and around the device and alert on deviations, especially outbound wget, curl, or reverse-shell patterns.
Monitor for repeated failed logins to the LK100W management interface that may precede credential-based exploitation.

How to Mitigate CVE-2026-78037

Immediate Actions Required

Restrict network access to the LK100W web management interface to trusted administrative networks or jump hosts only.
Rotate all LK100W management credentials and enforce strong, unique passwords for every account.
Review recent management-interface logins and investigate any sessions originating from unexpected sources.
Consult CISA ICS Advisory ICSA-26-239-01 for vendor-provided remediation guidance.

Patch Information

At the time of publication, no vendor patch URL is listed in the NVD entry. Refer to the CISA ICS Advisory ICSA-26-239-01 and the associated GitHub CSAF Document for the latest vendor remediation status. Apply firmware updates from Xiiaozet as soon as they become available.

Workarounds

Place the LK100W behind a firewall and block inbound access to the web management interface from untrusted networks, following ICS network segmentation guidance.
Disable remote management if not strictly required and require VPN access for administrative sessions.
Limit administrative accounts to the minimum set of users and remove default or shared credentials.
Implement network monitoring in front of the device to detect and alert on command injection payloads until a firmware fix is deployed.

bash

# Example: restrict access to the LK100W management interface to a trusted admin subnet
# (replace interface names and CIDRs to match the environment)
iptables -A INPUT -p tcp --dport 80  -s 10.10.20.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 10.10.20.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80  -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP