CVE-2025-41277: Waterfall WF-500 Firmware RCE Vulnerability

CVE-2025-41277 Overview

CVE-2025-41277 is an OS Command Injection vulnerability [CWE-78] in the Console WebUI of Waterfall Security WF-500 TX and RX Hosts running firmware version 7.9.1.0 R2502171040. Nozomi Networks Labs identified the flaw, which allows remote unauthenticated attackers to execute arbitrary operating system commands on the device. The WF-500 is a unidirectional security gateway commonly deployed at the boundary between operational technology (OT) and information technology (IT) networks. Successful exploitation compromises the integrity of the data diode appliance and can pivot attackers into protected industrial environments.

Critical Impact
Unauthenticated remote attackers can execute arbitrary OS commands on WF-500 unidirectional gateways, undermining the integrity boundary between IT and OT networks.

Affected Products

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

Discovery Timeline

Vulnerability discovered and reported by Nozomi Networks Labs
2026-05-29 - CVE-2025-41277 published to NVD
2026-06-01 - Last updated in NVD database

Technical Details for CVE-2025-41277

Vulnerability Analysis

The Console WebUI on the WF-500 TX and RX Hosts fails to properly neutralize special elements in user-supplied input that is passed to an underlying operating system shell. An attacker reaches the vulnerable endpoint over the network without authentication and supplies crafted parameters containing shell metacharacters. The Console WebUI then incorporates the attacker-controlled data into a command string executed by the host operating system. Because the WF-500 enforces a data diode between trusted and untrusted networks, command execution on the gateway itself undermines the device's core security guarantee. Refer to the Nozomi Networks Vulnerability Advisory for full technical details.

Root Cause

The root cause is improper neutralization of special elements used in an OS command [CWE-78]. The Console WebUI concatenates untrusted input into a shell command without sanitization, escaping, or use of parameterized execution primitives. Shell metacharacters such as ;, |, &, and backticks break out of the intended command context.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker with network reachability to the Console WebUI on a WF-500 TX or RX host sends a crafted HTTP request to the vulnerable endpoint. The injected commands run with the privileges of the web application process on the gateway appliance.

No verified proof-of-concept code is publicly available. See the vendor advisory for technical specifics rather than synthetic exploit code.

Detection Methods for CVE-2025-41277

Indicators of Compromise

Unexpected outbound network connections originating from WF-500 TX or RX hosts to attacker-controlled infrastructure.
Anomalous child processes spawned by the Console WebUI service, particularly shells (/bin/sh, /bin/bash) or system utilities (wget, curl, nc).
HTTP requests to Console WebUI endpoints containing shell metacharacters such as ;, |, &&, or URL-encoded equivalents (%3B, %7C, %26%26).
New or modified files in writable directories on the gateway that were not introduced by an authorized firmware update.

Detection Strategies

Inspect WF-500 management interface access logs for unauthenticated requests to Console WebUI endpoints with suspicious parameter values.
Deploy network monitoring at the IT-OT boundary to flag any unsolicited traffic egressing from WF-500 appliances.
Correlate firewall and IDS telemetry around the management VLAN to detect reconnaissance against the Console WebUI.

Monitoring Recommendations

Forward WF-500 syslog and web access logs to a centralized SIEM and alert on parameters containing command-injection metacharacters.
Baseline normal process and network behavior of the gateway and alert on deviations.
Monitor for repeated 4xx or 5xx responses on Console WebUI endpoints that may indicate exploitation attempts.

How to Mitigate CVE-2025-41277

Immediate Actions Required

Restrict network access to the WF-500 Console WebUI to a dedicated management network and a small set of administrative hosts.
Place the management interface behind a jump host with multifactor authentication and full session logging.
Apply the vendor-supplied fixed firmware as soon as Waterfall Security releases an update addressing CVE-2025-41277.
Audit WF-500 TX and RX hosts for signs of prior exploitation, including unexpected processes, files, and outbound connections.

Patch Information

Waterfall Security WF-500 TX and RX firmware version 7.9.1.0 R2502171040 is confirmed vulnerable. Consult the Nozomi Networks Vulnerability Advisory and Waterfall Security support channels for the fixed firmware build and upgrade procedure.

Workarounds

Block all network access to the Console WebUI from untrusted networks using upstream firewall rules until a patched firmware is deployed.
Disable the Console WebUI service when administrative changes are not actively being performed, if the deployment supports doing so.
Segment WF-500 management interfaces onto an out-of-band network unreachable from production IT and OT zones.

bash

# Example upstream firewall restriction (adapt to your environment)
# Allow Console WebUI access only from the management jump host
iptables -A FORWARD -p tcp -s 10.10.20.5/32 -d 10.20.30.10/32 --dport 443 -j ACCEPT
iptables -A FORWARD -p tcp -d 10.20.30.10/32 --dport 443 -j DROP