Retrieving "deleted" sms/mms from Nokia phone (Sym

[escalation666]

During some research, I found an intersting "feature"

on my Nokia mobile phone; I was able to retrieve any

apparently deleted sms/mms.

Letting aside some paranoid thoughts about WHY this

sms are not deleted, I think that, while this represents

an high risk for our privacy, this discover could give some

hint into mobile phone forensics and anti-forensics field.

First, I would like to tell you that I tested this on

my Nokia N-gage and on a Nokia 6600 but I am quiete sure

that this procedure works on every Nokia Symbian S60

(maybe other vendors). So I strongly incite you to test

it on your mobile phone and share the results.

Tested products:

Nokia N-gage, firmware version: V 4.03 26-11-2003 NEM-4

Nokia 6600

Maybe the whole S60 series.

Procedure:

Download the Nokia PC Suite for your mobile phone and make

a backup on your local hd.

I used PC Suite for Nokia N-Gage Version 1.0.0

http://www.nokia.com/pcsuite

It will create a huge number of ".dat" files in a specified

directory.

Download, install and start Cygwin. This is not required but

suggested, you could use an hexadecimal editor and a bit of

patience but using Cygwin is surely faster.

http://www.cygwin.com

Move into the backup directory.

$ ls -al | less

total 6016

drwx------+ 2 Administrator Nessuno 0 Feb 6 01:35 .

drwx------+ 7 Administrator Nessuno 0 Feb 5 23:00 ..

-rwx------+ 1 Administrator Nessuno 2972 Nov 27 2003 1.dat

-rwx------+ 1 Administrator Nessuno 22913 Nov 27 2003 10.dat

-rwx------+ 1 Administrator Nessuno 1062 Feb 16 2005 100.dat

-rwx------+ 1 Administrator Nessuno 3912 Aug 9 2005 1000.dat

-rwx------+ 1 Administrator Nessuno 2750 Aug 25 2005 1001.dat

-rwx------+ 1 Administrator Nessuno 8741 Dec 15 2005 1002.dat

-rwx------+ 1 Administrator Nessuno 9926 Dec 20 2005 1003.dat

-rwx------+ 1 Administrator Nessuno 63 Dec 30 2005 1004.dat

-rwx------+ 1 Administrator Nessuno 23988 Jan 13 2006 1005.dat

-rwx------+ 1 Administrator Nessuno 18 Jan 23 2006 1006.dat

...

...

etc etc (files created by the nokia pc suite).

Choose a file to examine.

$ ls -al 3102.dat

-rwx------+ 1 Administrator Nessuno 666569 Feb 5 23:59 3102.dat

Use the command "strings" to find printable characters.

$ strings 3102.dat | less

Ciao! Auguro a te ed alla tua fa@Enrica Farlonesi

...

...

etc etc

This is part of an sms I deleted and that I don't see on my phone.

So, just grep every file in the directory to find the complete sms:

$ grep -i "Auguro a te ed alla" *

Binary file 1770.dat matches

Binary file 3102.dat matches

The sms has been found in 1770.dat file, let's see what's inside it:

$ strings 1770.dat

Ciao! Auguro a te ed alla tua famiglia un felice anno nuovo! E.

4+393915253350

4+393922378986

Got it! The complete sms, with the phone number of the sender (phone

numbers have been changed).

In earlier versions of Nokia PC Suite it just creates a ".nbu" file and

you can just edit it with an hexadecimal editor.

I mailed the Nokia support and they told me they didn't know about this

bug and would like to know more informations about impacted models but

they don't have any intention to release some kind of patch.

I contacted Symbian too, they told me that Symbian sources are

distributed to mobile phone vendors and so they cannot release any

final-user patch.

This description is also avaiable here:

http://www.alighieri.org/advisories/retrieving_deleted_sms.txt (ENG)

http://www.alighieri.org/advisories/recuperare_sms_cancellati.txt (ITA)

Credits: Davide Del Vecchio