CSW Security Advisory 0002: Oral B SmartMonitor Information Disclosure Vulnerability and DoS

[craigswright () acm org]

Craig Wright Security Advisory 0002
http://gse-compliance.blogspot.com 
Jun 19, 2008

I. BACKGROUND

The Oral B Triumph Toothbrush with SmartGuide™
ProfessionalCare™ 9900 is designed to enhance your brushing experience with “while-you-brush” feedback. SmartGuide is 
designed to ensure that you always have the best brushing experience. 

http://www.oralb.com/us/products/power/triumphsmartguide/ 

II. DESCRIPTION

Remote exploitation of an information disclosure vulnerability in Oral B’s SmartGuide management system allows 
attackers to obtain sensitive information.

This vulnerability exists due to a lack of authentication between the toothbrush and the monitoring device. The simple 
association key is easily compromised allowing the toothbrush and monitoring device to be spoofed using by a malicious 
attacker.

There is also a possible wireless denial of service where a malicious attacker could stop the radio feedback and 
monitoring.

The trashbin feature of the SmartMonitor device does not overwrite deleted data.

III. ANALYSIS

Exploitation allows an attacker to gain sensitive information from the toothbrush. No authentication is required to 
reach the affected application. The attacker only needs to be able to monitor the wireless transmission.

The attacker can determine the users brushing habits. It is possible to report on the location of the mouth that is 
being brushed and the amount of time spent on each of four defined “quantrants”. 

An attacker could also conduct a serious DoS attack. Flooding the wireless communications causes the unit to stop 
responding. This can result in the following actions:
A.      A continued DoS could cause the bristle monitor to not send an end of life signal to the SmartMonitor system 
leaving the user to continue using an old toothbrush head which could eventually lead to dental failure. The failure to 
monitor the most effective head life could result in bristle failure.
B.      Dental statistics could be erased from the monitor unit. This would leave the user unable to determine and 
report on their brushing habits. This could lead to user confusion and over or under brushing leading to tooth wear.
C.      Fake battery life transmissions can be sent making the user believe that the battery life is in fact longer 
than is truly stored. This could lead to a catastrophic brushing failure where the toothbrush runs out of power in 
mid-clean. A continued long term attack could lead to the creation of cavities in the user’s teeth.  

A forensic analysis of the SmartMonitor unit can be conducted to recover deleted brushing sessions. A user who was 
attempting to cover a period of lapsed dental care could be investigated and the deleted data recovered. In some cases 
it is feasible that this could result in a reduction of user privileges and possible punitive action (especially where 
the analysis is conducted by the parent administrative body).

IV. DETECTION

The DoS attack is readily detectable as the toothbrush fails to communicate to the monitoring unit.

Monitoring and interception remains undetectable with no known means to monitor this insidious threat to user brushing 
privacy.

V. WORKAROUND

The vendor has a deactivation process that will allow the toothbrush to operate manually with the radio disabled.

VI. VENDOR RESPONSE

I was unable to get an adequate result from the vendor and the receptionist did not forward the calls after the first 
few. A direct call to the sales channel resulted in the comment, “who the hell would want to monitor a toothbrush”.

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has not assigned a name to this issue as yet. 

VIII. DISCLOSURE TIMELINE

19/06/2008  Initial vendor notification
19/06/2008  Initial vendor response
19/06/2008  Coordinated public disclosure

IX. CREDIT

Permission is granted for the redistribution of this alert electronically

Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently 
available information. Use of the information constitutes acceptance for use in an AS IS condition.

There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for 
any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.