CVE-2025-63353

FiberHome Wi-Fi Password Predictor (CVE-2025-63353)

A Python utility designed for security auditing and proof-of-concept demonstration of the deterministic password generation flaw found in FiberHome HG6145F1 (RP4423) routers.

📋 Overview

This script exploits CVE-2025-63353, a critical vulnerability where the factory-default WPA/WPA2 pre-shared key is mathematically derived from the broadcasted SSID. By observing the network name (SSID), an attacker can calculate the default password without any user interaction. The Vulnerability Logic: The router uses a deterministic formula: HEX_A (from SSID) + HEX_B (from Password) = 0xFFFFFF.

🌍 Global Impact

FiberHome equipment is widely deployed by major Internet Service Providers (ISPs) across emerging markets. This script is specifically effective against devices with the following default naming conventions:

• Vulnerable SSID Format: fh_XXXXXX (e.g., fh_96C3A0)
• Vulnerable Password Format: wlanxxxxxx

Affected Regions and ISPs

• Algeria: Algérie Télécom (Idoom Fibre).
• Philippines: PLDT.
• India: BSNL and Airtel.
• Indonesia: Telkom Indonesia.

🚀 Usage

The script uses argparse to handle command-line inputs.

Basic Command

python predictor.py fh_96C3A0

Output:

[+] Predicted Password: wlan693c5f

Verbose Mode

Use the -v flag to see the underlying hexadecimal subtraction.

python predictor.py fh_96C3A0 -v

Output:

[*] Input HEX_A: 0x669EA0
[*] Calculation: 0xFFFFFF - 0x669EA0 = 0x99615F
[+] Predicted Password: wlan693c5f

🛠️ Mitigation for Users

If your router is affected, your network is insecure until you take action:

1. Change your Wi-Fi Password: Do not use the factory-default settings.
2. Disable WPS: This reduces the attack surface for similar credential-based exploits.
3. Use a Third-Party Router: Connect your own router to the FiberHome ONT and disable the FiberHome Wi-Fi entirely.

⚠️ Legal Disclaimer

This information is provided for authorized security testing, network administration, and educational purposes.