Security Advisory

MSL-2009-001 - Samsung Missing Provisioning Authentication



Advisory Information
--------------------
Title:	Samsung Missing Provisioning Authentication

Advisory ID:		
MSL-2009-001

Advisory URL:
http://www.mseclab.com/index.php?page_id=148

Published:
2009-04-23

Updated:
2009-04-23

Vendor:
Samsung 


Vulnerability Details
---------------------
Class:
Authentication Bypass

Remote:
Yes

Local:
No

Public References:
Not Assigned

Affected:
Samsung M8800 Innov8
Samsung SGH-J750


Not Affected:
Unknown

Description:
Affected devices do not perform proper authentication of incoming SMS Provisioning messages.

The following behaviors have been verified on affected devices:

1.Source of provisioning message is never displayed to user.

2.Unauthenticated SMS Provisioning messages, where SEC and MAC parameters are not present in the message, are accepted. User is not made aware that the received provisioning message is not authenticated.

3.Authenticated SMS Provisioning messages, where SEC and MAC parameters are present in the message, are accepted, but the parameters are not used for performing the security checks.

More specifically:

USERPIN authenticated provisioning message: device installs the received configuration without performing any message authentication. PIN Code is never asked to user and is not required for completing the installation. The installation is correctly performed and the configuration is installed as default.

NETWPIN authenticated provisioning messages: device installs the received configuration without performing any message authentication. Sender does not need to know the correct IMSI value in order to let the device accepts the message as correct. The configuration will be installed regardless of the MAC value present in the message.

By sending provisioning messages in one of the above specified ways, an attacker could pose as a legitimate trusted source and entice a victim into installing a malicious configuration.
Such an attack could lead to the hijacking of mobile data connections originated  by the device. 
 
 

Solutions & Workaround:
Not available


Additional Information
----------------------

Timeline:
2009-04-04: Issue discovery
2009-04-06: Initial Vendor Notification: Point of Contact requested via contact form on website (No suitable e-mail available)
2009-04-07: Vendor Response: Automated response
2009-04-23: Public Disclosure

Vendor Statement:
None