The majority of financial service professionals considers Man In The
 Browser as the greatest threat to online banking, cybercrime increases 
its use.
Man In The Browser attack, 
DDoS attacks, 
phishing
 are most insidious cyber threats against banking institutions. Last 
statistics proposed by principal security firms confirm that online 
banking is considered a lucrative business for 
cybercrime.
The large diffusion of online banking platforms, their openness to mobile and 
social networking
 platforms are attracting the attention of cyber-criminals that are 
concentrating their effort against online banking services. The first 
form of attacks was considered phishing, using social engineering tricks
 crocks are able to obtain banking credentials from unaware banking 
customers.
Unfortunately also malware authors concentrated their efforts to hit 
the growing sector developing new malicious code able to steal banking 
credentials from victims often including key-loggers agent and screen 
grabbing modules.
The response of banking world was the improvement of 
authentication processes,
 a classic example is represented by rapid diffusion for multi-factor 
authentication such as OTPs (e.g. One-time passwords device/service 
(SMS, email), a hardware token).
The cybercrime ecosystem has widely used the man-in-the-browser 
attacks to overtake defense systems, let’s see what it is and which are 
the countermeasure that could be really effective for user’s security. 
 The majority of financial institutions in numerous surveys has 
considered Man In The Browser as the greatest threat to online banking. 
In the classic scheme for the “
Man in the Middle”
 attack the attacker lies between the victim client and the banking 
server, it’s clear that the introduction of encrypting traffic could 
make ineffective the technique.
In the Man-in-the-browser schema the attackers integrate the concept 
proper of the above methods with the use of malicious code that infects 
victims client component such as the browser. Usually MITB appears in 
the 
form of BHO (Browser Helper Object
)/Active-X Controls/Browser Extension/Add-on/Plugin/ API – Hooking.
Man-in-the-browser attack is based on the presence on the victim 
machine of a proxy malware that infects the user’s browser exploiting 
its vulnerabilities. The malware is able to modify transaction content 
or conduct operations for the victims in a completely covert fashion. 
The malware is usually able to hide its transactions to the client 
altering the content proposed by the browser.
The malware is able to bypass multi-factor authentication, once the 
bank website authenticates the user that has provided the correct 
credentials the Trojan horse waits for the transactions to modify its 
content. The malicious code is also able to provide evidence of the 
success of the user’s transaction altering the content displayed by the 
browsers once executed.
The Man In The Browser attack is a very insidious because neither the
 bank nor the user can detect it, despite a multifactor authentication 
process, 
CAPTCHA
 or other forms of challenge response authentication are 
implemented. Security experts find that most Internet users (73%) cannot
 distinguish between real and fake pop up warning messages neither have 
possibility to distinguish malware crafted content.
The majority of financial service professionals in a survey 
considered Man In The Browser to be the greatest threat to online 
banking, malware such as 
Zeus, 
Carberp, Sinowal  and Clampi have inbuilt MITB capabilities. Recently a Trusteer’s security team identified a new instance of the 
Ramnit malware that uses the 
HTML injection to target the digital distribution platform for online gaming Steam.
Unfortunate end-users 
are
 still vulnerable to Man In The Browser attacks, their unique 
responsibility it to try to limit the occasions of exposure to attacks 
(e.g. Phishing) that could allow the infection of their system.
The most efficient countermeasure is considered out of Band 
transaction verification containing transaction details along with OTP 
and on bank side the adoption of a Fraud detection based on User 
behavior profiling.
In the following table a useful table that resume principal 
countermeasures adopted against a Man-in-the-browser attack and their 
real effectiveness.