Skip to main content

Vodafone India privacy problem: exposes phone numbers

Vodafone India is exposing website surfer/user's phone number to the partner website when using mobile data plan. It might be offering hidden API to those partner websites to uniquely identify users. I have noticed it around 1-year before, thought about blogging, but forgot it at that time. Now, I have got some time and so thought of explaining the issue.

How I noticed the issue?

Sometime ago, I've bought SanDisk microSD card. In the wrapper, they've mentioned about some offer about hungama (Still available in SanDisk website at www.sandisk.in/campaign/landing/hungama/offer_three). The URL mentioned was offers.hungama.com/sandisk3/ and when I opened that in my mobile browser, it was prompting with Welcome, 91-98XXXXXXXX.
Phone number leaked by Vodafone India


I was shocked as I never seen anything like that before. So, I immediately opened the same URL in my desktop browser and got completely different page:
Desktop version of the same page

And, again I tried to open the same page in mobile browser with Wi-Fi alone (by disabling Mobile Data), and now also they couldn't identify my mobile number. So, I realized that it might be something to do with the network (Vodafone). Initially I thought that they may be decoding the phone number from IP address. So, I asked Heleena (my wife) to figure out some pattern for that. Then it turn out that there is no definite pattern. I have also analyzed HTTP headers when browsing through Vodafone internet. Then, realized that hungama might be utilizing some hidden API from Vodafone to decode user's IP to mobile number.

Privacy Issue


At least for me, this looks like a serious privacy issue. hungama at least openly exposes the phone number to users, so that users can know that hungama can read their numbers/identity. But, there may be many sites--especially many social media sites such as Facebook, Twitter, Google, etc may still be uniquely identifying users without revealing it at all. 

Labels

Labels:

Comments

Ohmkumar said…
Hi Rajesh,
Welcome back :)

Hope you agree, nothing is private in online...
May 1, 2016, 3:52:00 PM
Post a Comment

Popular posts from this blog

BehaviorS.js - An alternative to Behaviour.js, event:Selectors and Low Pro libs for unobtrusive JavaScript programming

BehaviorS.js yet another unobtrusive JavaScript library similar to Behaviour.js and event:Selectors but in implementation uses hash based lookup without extending elements; so presumably it should be faster than the rest. The original script and idea was by JLof ; I extended it for DOMContentLoaded support, optimized a bit to avoid scanning of more depths, and added new rules support. I wanted to document the plug a long time and just got time to do it. For the time being BehaviorS.js is available here Update (2006-09-11) : Coralized the link to BehaviorS.js so as to save the load on free brinkster.com webpage Update (2006-09-27) : If the coralized link to BehaviorS.js doesn't work, use http://www21.brinkster.com/guideme/BehaviorS/
17 comments
Read more

Interview question #1

Since I have been asked to interview experienced PHP programmers, I was preparing few interview questions. I came to know, most of the people ask questions found in the Internet; most of them are like "What is the function used to connect MySQL DB in PHP". Personally, I don't like these types of questions; I'd thought the person must apply ideas what he was taught in colleges--finally I came out with one question: A product vendor has Quantity Vs. Price data like 1 -> Rs. 50 2 -> Rs. 95 3 -> Rs. 140 .... like upto 1 million data. He wants a system, which gives the price when the quantity is provided. For example, if you provide the quantity value as 2, then it should provide Rs. 95. How this system can be designed? As expected, all the people said about using database tables and quering on quantity. I have asked them to find out a system which doesn't use databases--provided the accuracy of the system may not be 100%--it may give at least 90% ac...
7 comments
Read more