A recent high-profile forensic investigation reported that “due to end-to-end encryption employed by WhatsApp, it is virtually impossible to decrypt the contents of the downloader [.enc file] to determine if it contained any malicious code in addition to the delivered video.”
This project demonstrates how to decrypt encrypted media files downloaded from WhatsApp.
$ go get github.com/ddz/whatsapp-media-decrypt
Usage of whatsapp-media-decrypt:
-o file
write decrypted output to file
-t type
media type (1 = image, 2 = video, 3 = audio, 4 = doc)
$ whatsapp-media-decrypt -o Atzc5Drr8l7ngis8GmUTMI6vMQNjOU9zGQ2SYRkjwq44.mp4 -t 2 Atzc5Drr8l7ngis8GmUTMI6vMQNjOU9zGQ2SYRkjwq44.enc 0A2069A349914734B9359DA0CD8923E6DFDE06F1E2BCE23222C738C521570BA8242A1220A1F5AEB2E620F73007FA853200559B2669455BB5818F619397C638042D8F7F2A18B984A5F1052000
(Left as an exercise for the reader)
$ sqlite ChatStorage.sqlite
SQLite version 3.27.2 2019-03-09 15:45:46
Enter ".help" for usage hints.
sqlite> select ZMEDIAURL,ZVCARDSTRING,hex(ZMEDIAKEY) from ZWAMEDIAITEM where Z_PK = 1795;
https://mmg-fna.whatsapp.net/d/f/Atzc5Drr8l7ngis8GmUTMI6vMQNjOU9zGQ2SYRkjwq44.enc|video/mp4|0A2069A349914734B9359DA0CD8923E6DFDE06F1E2BCE23222C738C521570BA8242A1220A1F5AEB2E620F73007FA853200559B2669455BB5818F619397C638042D8F7F2A18B984A5F1052000
sqlite> .quit
$ curl -O https://mmg-fna.whatsapp.net/d/f/Atzc5Drr8l7ngis8GmUTMI6vMQNjOU9zGQ2SYRkjwq44.enc
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 389k 100 389k 0 0 1966k 0 --:--:-- --:--:-- --:--:-- 1956k
$ whatapp-media-decrypt -o Atzc5Drr8l7ngis8GmUTMI6vMQNjOU9zGQ2SYRkjwq44.mp4 -t 2 ./Atzc5Drr8l7ngis8GmUTMI6vMQNjOU9zGQ2SYRkjwq44.enc 0A2069A349914734B9359DA0CD8923E6DFDE06F1E2BCE23222C738C521570BA8242A1220A1F5AEB2E620F73007FA853200559B2669455BB5818F619397C638042D8F7F2A18B984A5F1052000