Kali Linux has unveiled two innovative packages—brcmfmac-nexmon-dkms and firmware-nexmon—designed to significantly enhance wireless penetration testing capabilities for Raspberry Pi users. These additions enable the onboard Wi-Fi interfaces of supported Raspberry Pi models to perform monitor mode operations and frame injection without the need for external USB adapters, marking a substantial advancement for cybersecurity professionals and ethical hackers who rely on portable testing setups.
Addressing Previous Limitations
Historically, Raspberry Pi users faced challenges in conducting wireless security assessments due to the inherent limitations of Broadcom/Cypress Wi-Fi chipsets, which lacked support for monitor mode and injection capabilities. This necessitated the use of external USB Wi-Fi adapters, adding complexity and reducing the portability of penetration testing setups.
Integration with the Nexmon Project
The breakthrough is achieved through integration with the Nexmon project, a C-based firmware patching framework developed by SEEMOO Lab at TU Darmstadt. Nexmon modifies Broadcom’s closed firmware binaries and provides patches for the Linux driver (brcmfmac), enabling advanced wireless functionalities. This collaboration has been instrumental in extending the capabilities of Raspberry Pi’s onboard Wi-Fi interfaces.
Details of the New Packages
– brcmfmac-nexmon-dkms: This package offers a DKMS-based version of the brcmfmac driver with Nexmon patches. The DKMS (Dynamic Kernel Module Support) implementation ensures that the driver rebuilds against the kernel during installation, maintaining compatibility across system updates.
– firmware-nexmon: This package delivers Nexmon-patched firmware for supported Broadcom chips, enabling the enhanced wireless capabilities.
Supported Raspberry Pi Models
The new packages have been tested and confirmed to work on various Raspberry Pi models, including:
– Raspberry Pi 5 (64-bit)
– Raspberry Pi 4 (both 64-bit and 32-bit)
– Raspberry Pi 3B (both architectures)
– Raspberry Pi Zero 2 W (43436s variant)
– Raspberry Pi Zero W
Installation Instructions
For users running Kali Linux on Raspberry Pi systems, installing the new packages is straightforward:
1. Update the package list:
“`bash
sudo apt update
“`
2. Upgrade existing packages:
“`bash
sudo apt full-upgrade -y
“`
3. Install the new packages:
“`bash
sudo apt install -y brcmfmac-nexmon-dkms firmware-nexmon
“`
4. Reboot the system to apply changes:
“`bash
sudo reboot
“`
Evolution of Kali Linux’s Integration with Nexmon
Kali Linux’s integration with Nexmon has evolved over time. The development team previously operated on the 5.15 kernel series for an extended period due to packaging complexities and patchset management challenges. Attempts to migrate to kernel 6.6 encountered stability issues, prompting developers to pause development until a more reliable approach could be implemented. The transition to the 6.12 kernel provided an opportunity to rebuild the integration properly, resulting in the current stable packages. This move also enables support for newer devices like the Raspberry Pi 5, which requires more recent kernel versions.
Implications for Wireless Penetration Testing
The introduction of these packages eliminates a significant barrier for portable wireless assessments. Security professionals can now utilize tools like aircrack-ng, aireplay-ng, and other wireless penetration testing utilities directly with the Raspberry Pi’s built-in Wi-Fi interface. This capability is particularly valuable for conducting wireless security audits, testing network encryption strength, and performing frame injection attacks for legitimate security research.
Collaborative Effort
This development represents a collaborative effort between the Kali Linux team, the Nexmon project researchers at SEEMOO Lab, and community contributors who helped test and refine the packages. It underscores Kali Linux’s commitment to providing cutting-edge tools for cybersecurity professionals while expanding the capabilities of affordable, portable penetration testing platforms.
