I've again ventured outside my area of competence, so I'd ask for advise. :) I have a project that uses packet injection and packet capture over WiFi interfaces (and Ethernet too, actually, but that's a side story). So far, I have used Alfa USB wireless cards, but they are huge (4 antennas, footprint as big as Pi4) and somewhat slow (USB bandwidth most likely).
I know that Raspberry Pi Zero 2 can enter monitor / inject mode under Kali Linux. Their release 2025.3 seems to have re-introduced support for "nexmon" firmware. Source of claim: https://cybersecurefox.com/en/kali-linu ... r-hacking/
I know that with effort, it is possible to compile Nexmon firmware under the Raspberry Pi OS also (I have done it once around 2018 or so), but Nexmon is very picky about kernels. Their table currently says:
bcm43436b03 9_88_4_65 Raspberry Pi Zero 2 W Raspberry Pi OS Kernel 5.10
...but the current kernel is already:
Linux dev 6.12.47+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.12.47-1+rpt1~bookworm (2025-09-16) aarch64 GNU/Linux
I see 3 pathways:
1. switch to Kali Linux (losing "pigpio" and Pi-specific camera features, which are irreplaceable for me) --> dead end
2. bring the sources of a 6.12 kernel into compatibility with Nexmon --> far beyond my competence, I'm not a kernel dev
3. downgrade the Raspberry Pi OS kernel to the version required by Nexmon --> seems realistic
Can anyone tell, is it possible to downgrade to 5.10 on Bookworm Lite? What would be the shortest path to get it done? When I search for "linux-image" with "aptitude", I only get matches for version 6.x kernels? Do I have to downgrade from Bookworm to Bullseye?
Alternatively, if I first installed the exact same kernel version that Kali uses (6.12.34) and then crudely copied over some binaries from "lib/modules/6.12.34+rpt-rpi-v7l/kernel/drivers/net/wireless/" - what would be the chance of monitor mode working on the Raspberry Pi OS?
I know that Raspberry Pi Zero 2 can enter monitor / inject mode under Kali Linux. Their release 2025.3 seems to have re-introduced support for "nexmon" firmware. Source of claim: https://cybersecurefox.com/en/kali-linu ... r-hacking/
I know that with effort, it is possible to compile Nexmon firmware under the Raspberry Pi OS also (I have done it once around 2018 or so), but Nexmon is very picky about kernels. Their table currently says:
bcm43436b03 9_88_4_65 Raspberry Pi Zero 2 W Raspberry Pi OS Kernel 5.10
...but the current kernel is already:
Linux dev 6.12.47+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.12.47-1+rpt1~bookworm (2025-09-16) aarch64 GNU/Linux
I see 3 pathways:
1. switch to Kali Linux (losing "pigpio" and Pi-specific camera features, which are irreplaceable for me) --> dead end
2. bring the sources of a 6.12 kernel into compatibility with Nexmon --> far beyond my competence, I'm not a kernel dev
3. downgrade the Raspberry Pi OS kernel to the version required by Nexmon --> seems realistic
Can anyone tell, is it possible to downgrade to 5.10 on Bookworm Lite? What would be the shortest path to get it done? When I search for "linux-image" with "aptitude", I only get matches for version 6.x kernels? Do I have to downgrade from Bookworm to Bullseye?
Alternatively, if I first installed the exact same kernel version that Kali uses (6.12.34) and then crudely copied over some binaries from "lib/modules/6.12.34+rpt-rpi-v7l/kernel/drivers/net/wireless/" - what would be the chance of monitor mode working on the Raspberry Pi OS?
Statistics: Posted by diastrikos — Mon Oct 13, 2025 2:18 am