Using Aircrack
aircrack-ng input.cap -J hashcat_output
Unfortunately the above command doesn’t seem to work anymore.
If you try to run Hashcat with the outputted file you’ll get an error.
hashcat_output.hccap: Old hccap format detected! You need to update: https://hashcat.net/q/hccapx
Using Hashcat utils
Refer to this guide for installing the Hashcat utils.
Basic syntax is
./cap2hccapx.bin input.cap output.hccapx
Example
~/Downloads/hashcat-utils-master/src/cap2hccapx.bin aircrack-01.cap aircrack.hccapx