CVE-2025-41267: Waterfall WF-500 Firmware RCE Vulnerability

CVE-2025-41267 Overview

CVE-2025-41267 is an OS command injection vulnerability in the Administration WebUI of the Waterfall WF-500 TX Host. Nozomi Networks Labs identified the flaw in firmware version 7.9.1.0 R2502171040. The issue is tracked as [CWE-78]: Improper Neutralization of Special Elements used in an OS Command. Remote authenticated attackers can execute arbitrary operating system commands on the WF-500 TX Host. The WF-500 is a unidirectional security gateway widely deployed in operational technology (OT) and industrial control system (ICS) environments to enforce data diodes between trust zones.

Critical Impact
Authenticated attackers reaching the Administration WebUI can execute arbitrary OS commands on the WF-500 TX Host, compromising the integrity of a device that enforces network segmentation between OT and IT networks.

Affected Products

Waterfall Security WF-500 hardware appliance
Waterfall Security WF-500 firmware version 7.9.1.0 R2502171040
WF-500 TX Host Administration WebUI

Discovery Timeline

Vulnerability identified by Nozomi Networks Labs
2026-05-29 - CVE-2025-41267 published to NVD
2026-06-01 - Last updated in NVD database

Technical Details for CVE-2025-41267

Vulnerability Analysis

The vulnerability resides in the Administration WebUI of the WF-500 TX Host, the transmit side of Waterfall's unidirectional gateway. The WebUI fails to neutralize special shell metacharacters before passing user-supplied input to an underlying operating system command interpreter. An authenticated attacker with WebUI access can inject shell directives that the host executes with the privileges of the calling service. Successful exploitation breaks the security boundary the WF-500 is designed to enforce. Attackers can pivot to alter forwarding configuration, exfiltrate credentials, or stage tooling on the appliance.

Root Cause

The root cause is improper neutralization of special elements in input handled by the Administration WebUI ([CWE-78]). Input fields reachable through authenticated WebUI endpoints flow into shell command construction without adequate sanitization, escaping, or parameterized execution. Concatenating untrusted input into a command string passed to a shell allows metacharacters such as ;, |, &, backticks, and $() to alter the intended command.

Attack Vector

Exploitation requires network access to the Administration WebUI and high-privilege authenticated credentials. User interaction is also required, indicating the attack path likely involves an administrator action against a crafted payload stored or supplied through the interface. The attacker delivers a payload containing shell metacharacters through a WebUI parameter. The TX Host then executes the injected commands, granting arbitrary OS command execution on a device positioned at a critical OT/IT boundary.

No public proof-of-concept code is available, and no verified exploit samples have been released. Refer to the Nozomi Networks Vulnerability Advisory for technical details.

Detection Methods for CVE-2025-41267

Indicators of Compromise

Unexpected child processes spawned by the WF-500 WebUI service, especially shell interpreters or networking utilities such as sh, bash, nc, curl, or wget.
Administration WebUI request logs containing shell metacharacters (;, |, &, backticks, $()) within parameter values.
Outbound connections from the WF-500 TX Host to unrecognized IP addresses or domains.
New or modified files in administrative or temporary directories on the TX Host.

Detection Strategies

Inspect WebUI access logs for authenticated sessions issuing requests with anomalous input lengths, encoded payloads, or command-injection signatures.
Baseline expected process trees on the WF-500 TX Host and alert on deviations originating from web service parent processes.
Correlate administrator authentication events with subsequent configuration changes or process executions on the appliance.

Monitoring Recommendations

Forward WF-500 syslog and WebUI audit events to a centralized log platform for correlation against known command-injection patterns.
Monitor north-south and east-west traffic from the WF-500 management interface for unexpected outbound flows.
Track privileged account usage on the Administration WebUI and alert on logins from unusual source addresses or outside maintenance windows.

How to Mitigate CVE-2025-41267

Immediate Actions Required

Restrict network access to the WF-500 Administration WebUI to a dedicated management VLAN reachable only from hardened jump hosts.
Rotate credentials for all administrative accounts on the WF-500 TX Host and enforce strong, unique passwords.
Review WebUI audit logs for evidence of suspicious authenticated activity since the affected firmware was deployed.
Contact Waterfall Security support to confirm fixed firmware availability and an upgrade plan.

Patch Information

The vulnerability affects WF-500 firmware version 7.9.1.0 R2502171040. Refer to the Nozomi Networks Vulnerability Advisory and Waterfall Security support channels for the remediated firmware release and upgrade instructions.

Workarounds

Place the Administration WebUI behind a network access control list that permits only specific administrative source IP addresses.
Limit the number of accounts with high-privilege WebUI access and apply the principle of least privilege.
Require multi-factor authentication on the upstream jump host used to reach the WF-500 management interface.
Disable or block external access to the Administration WebUI until the firmware is updated.

bash

# Example: restrict management access at the upstream firewall
# Replace addresses with your environment's management subnet and appliance IP
iptables -A FORWARD -s 10.10.20.0/24 -d 10.50.1.10 -p tcp --dport 443 -j ACCEPT
iptables -A FORWARD -d 10.50.1.10 -p tcp --dport 443 -j DROP