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Sunday, March 24, 2013
HDFC Bank website Vulnerable to ID Theft and Account Blackade
Indian Security Researcher Jiten Jain today revealed that
one of the Largest Private Banks in India, HDFC Bank’s e-Banking
website could be easy target of Unique type of Denial of Service
Attack which could result in blocking of e-banking accounts of all its
customers. Here is the detailed report of vulnerability submitted by
him.
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The NetBanking service of HDFC Bank, Which is one of the largest and
most reputed Banks in India, is completely vulnerable to ID theft,
Targeted phishing and Mass Account Blockade. HDFC bank has implemented
an extra security solution called 'Secure Access' on its website but
instead it has given a hidden door to hackers to block all HDFC
NetBanking accounts. 'Secure Access' is an additional layer of security
implement on HDFC Bank website is essentially a solution protecting your
account from hackers and fraudsters. Secure Access, an online security
initiative is intended to make NetBanking transactions safer by
protecting users from phishing websites and Hackers and help users
authenticate original HDFC website. HDFC Bank's NetBanking login is now a
two-step process with Secure Access image and text verification. Let us
take you through the steps involved in Secure Access and how it intends
to protect NetBanking account of HDFC customers.
Let us take you through the steps involved in Secure Access and how it intends to protect NetBanking account of HDFC customers.
1) In First Step User has to provide his customer-id (User Id) on the first screen
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| Image Protected By Devilz-Code.blogspot.com |
2) User is then taken to the next screen where he is shown his
personalized picture and message and asked to enter his IPIN (password).
Demo presentation of secure access work can be seen on HDFC website at following URL http://www.hdfcbank.com/assets/demo/secure_access.swf
Secure Access which is claimed to be Multi-layered Authentication
Process mandatory requires HDFC NetBanking users to register for it if
they want to conduct ANY Third Party Transactions like Transferring
Money, booking movie tickers, recharging phone.
During the research on HDFC Mobile Banking application and NetBanking
Portal it was discovered that while implementing Secure Access HDFC Bank
has compromised on the first and foremost principle of user
authentication on any Banking website i.e. Never reveal whether its User Name or the password which is incorrect in case wrong combination is entered.
Since Secure access implementation requires user to only enter his Customer ID (The fixed user name in case of HDFC bank NetBanking users. The system then checks at the backend if the user is registered for Secure Access or NetBanking, if user is not a registered or valid user, Customer id is asked again. But in case if the customer id is found to be correct and registered, User is taken to second step and shown his secure access image and text he selected and asked to enter is password.
Since Secure access implementation requires user to only enter his Customer ID (The fixed user name in case of HDFC bank NetBanking users. The system then checks at the backend if the user is registered for Secure Access or NetBanking, if user is not a registered or valid user, Customer id is asked again. But in case if the customer id is found to be correct and registered, User is taken to second step and shown his secure access image and text he selected and asked to enter is password.
1.) 1 Now this 1st step of verifying customer id and showing
personalized secure access image and text has made HDFC Bank vulnerable
to Blind customer id collection. We exploited this vulnerability by
running an automated suite with by generating random customer ids in a
sequence (example from 434XXXX to 515XXXXXX) and logged on HDFC
NetBanking website using them. The customer ids which showed secure
access and image and text were noted and rest was discarded. The secure
Access images and text which was shown for valid customer ids were also
saved. Now by the process above we were able to achieve 3 things. It was
shocking to see that secure text was displayed as simple text and not a
text image.
By this automated first step of Login, we were able to create a Database of several customer Ids of HDFC NetBanking users. We
could have made a complete database of every NetBanking users but since
this trial was conducted with a motive of checking security on banking
site, only a sample data was collected. We decided to destroy this data
later after completing this Demonstration.
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| Image Protected By Devilz-Code.blogspot.com |
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| Customer Id, Personalized Image and Text of Customer in above Screenshots has been hidden for security |
2) We then setup a phishing portal for HDFC Net banking and
created a fake HDFC NetBanking Mobile app and tried it on some people.
In our fake HDFC mobile application and phishing portal we were able to
replicate exactly same Secure Access behavior like on original HDFC
website using the database of Customer IDs of NetBanking users and their
secure Access image and text we had created earlier. Since our site was
showing the same secure Access images and text on entering customer ids
we used their security feature to provide more authentic look to our
phishing website and Mobile application. The Situation was worse for
fake mobile app since Mobile users could not even see the URL, setting
aside any chance of doubt in mind of user. Several users trusted our
phishing site and mobile app and tried to log in with their passwords.
3) Now in a third Killing step we launched denial of service
attack on website the by blocking some user accounts. Since Secure
Access authentication vulnerability has helped us create the database of
customer ids of HDFC NetBanking users we launched another program which
simple went on HDFC NetBanking website and provided customer id from
our database on HDFC NetBanking login page.
As we were providing valid Customer Id's, when asked for IPIN/Password we entered it incorrectly 5 times which resulted in those customers being blocked from NetBanking. We used chain proxy to bypass time and Sequence checks but were surprised to find out that HDFC site had NONE and we were able to easily block several user accounts.
As we were providing valid Customer Id's, when asked for IPIN/Password we entered it incorrectly 5 times which resulted in those customers being blocked from NetBanking. We used chain proxy to bypass time and Sequence checks but were surprised to find out that HDFC site had NONE and we were able to easily block several user accounts.
Since we were guided by ideology of ethical hacking we conducted above
research on a sample data But This flaw in authentication can be easily
used by anyone to generate a Database of Customer Ids of HDFC NetBanking
Users and completely Block all NetBanking accounts of all HDFC
NetBanking users. The same may be the used by the miscreants or
competitors of HDFC bank to hold literally entire NetBanking service of
HDFC bank for ransom by repeatedly blocking accounts even if they are
enabled again. This vulnerability also raises a big question, Are We
forgetting basic principles of Security in race of trying security
solution?
x--x--x
While Speaking to “The Hacker News” ,Mr. Jiten disclosed
that had shared the above vulnerability report with the HDFC Bank in
February itself to provide them ample time to fix the above
vulnerability. The report about lacking security on HDFC online banking
website is another blow to HDFC Bank which is already facing flak for
its shady deals and is currently under a Black Money investigation by
Indian Government.



