Now cybercriminals from Brazil are also interested in Bitcoin currency. In order to join the horde of phishers on the lookout for the virtual currency they have applied their best malicious technique: malicious PAC on web attacks, and phishing domains.

The malicious usage of PAC (Proxy Auto-Config) among Brazilian black hats is not something new – we’ve known about it since 2007. Generally, these kind of malicious scripts are used to redirect the victim’s connection to a phishing page of banks, credit cards and so on. We described these attacks in detail here. In 2012 a Russian Trojan banker called Capper also started using the same technique. When it’s used in drive-by-download attacks, it becomes very effective.

After registering the domain java7update.com, Brazilian criminals started attacking several websites, inserting a malicious iframe in some compromised pages:

Microsoft recently announced the shutdown of its popular IM client MSN Messenger, which will be replaced by Skype, but its end represents the beginning of malicious attacks posing as the installer of the software. Cybercriminals already started to use this fact in their attacks, registering malicious domains, buying sponsored links on search engines, tricking users to download and install a malware masquerade as the MSN installer.

MSN Messenger is still very popular in several countries; Microsoft informed that the service has more than 100 million users worldwide, approximately 30.5 million of them in Brazil. As an escalated migration of all users is planned, it's getting harder to find the installer of the program and this is the window of opportunity exploited by Brazilian cybercriminals aiming to infect users looking for the software.

In a simple search on Google for "MSN messenger" the first result displayed is sponsored link of a malicious domain aiming to distribute the fake installer, which is actually a Trojan banker:

Google Chrome users are being targeted these days by a wave of attacks that uses malicious extensions hosted in the official Chrome Web Store. The attack appears to be of Turkish origin and is using Facebook to spread. We saw users of different nationalities infected with the malicious extensions, which the cybercriminals are sending to the official store regularly, in a cat-and-mouse game.

As we already reported in March 2012, Brazilian cybercriminals were able at that time to host a malicious extension in the Chrome Web Store. Since then in June 2012 Google has changed the way users can add third party browser extensions i.e. not allowing the installation that are not hosted on the official Web Store. More recently Google removed the possibility of silent installations, which has been widely abused by third parties.

Maybe for these reasons bad guys started to concentrate their efforts to upload bad extensions to the official store. Now it’s the turn of Turkish cybercriminals; they were able to host several extensions there in the last few days.

Brazilian cybercrime is based primarily on the spread of Trojan bankers. For some time now the country’s bad guys have been investing their efforts in new monetization schemes, the latest includes the use of adware. And the perfect place for distributing this sort of malware? Yes, that’s right – social networks. This is how "PimpMyWindow", an adware and click-fraud scheme that has infected several Brazilian Facebook users in recent days, works.

To spread quickly among innocent users the adware uses a "change the color of your profile" option that recently surfaced. The infected profiles are used to spread automatic messages to your Facebook contacts:

How easy is it for bad guys to buy valid digital certificates from CAs using fake data and then start signing Trojan bankers with them? In Brazil it appears to be very easy.

Today most software developers digitally sign their programs. The process involves Certification Authorities (CAs) that must verify the authenticity of the files and issue a certificate to the developers.

As we know, valid or stolen digital certificates are used by some malware authors to create files that can go undetected for some time and be recognized as legitimate. Now Brazilian cybercriminals have started using this technique in their malware in an attempt to gain more time to spread files undetected. Recently we found a Trojan banker signed with a valid digital certificate issued by a CA. It appears that fake company data was used to obtain the certificate.

How easy is it for a CA to check if the data they receive is legitimate or not? Brazilian cybercriminals registered a domain called gastecnology.org, copying the name of a well-known and trusted local software company. This is the data used to register the domain:

Since November 2011, according to recent statistics, Google Chrome has become the most popular browser in Brazil (more than 45% of the market share).

The same has is true for Facebook, which now is the most popular social network in Brazil, with a total of 42 million users, displacing Orkut.

These two facts are enough to motivate Brazil’s bad guys to turn their attentions to both platforms. This month we saw a huge wave of attacks targeting Brazilian users of Facebook, based on the distribution of malicious extensions. There are several themes used in these attacks, including “Change the color of your profile” and “Discover who visited your profile” and some bordering on social engineering such as “Learn how to remove the virus from your Facebook profile”:

1) Click on Install app, 2) Click on Allow or Continue, 3) Click on Install now, After doing these steps, close the browser and open again

This last one caught our attention not because it asks the user to install a malicious extension, but because the malicious extension it’s hosted at the official Google's Chrome Web Store. If the user clicks on “Install aplicativo” he will be redirected to the official store. The malicious extension presents itself as “Adobe Flash Player”:

You’ve probably already heard about the 'Chupa Cabra', literally a "goat sucker". It’s a mythical beast rumored to inhabit parts of the Americas. In recent times it has been allegedly spotted in Puerto Rico (where it was first reported), Mexico and the United States, especially in the latter’s Latin American communities. The name Chupa Cabra has also been adopted by Brazilian carders to name skimmer devices, installed on ATMs. They use this name because the Chupa Cabra will “suck” the information from the victim’s credit card.

The Brazilian media regularly shows videos of bad guys installing their Chupa Cabra onto an ATM. Some of them are unlucky, or incompetent, and get picked up on security cameras and caught by the cops.

That’s what makes installing an ATM skimmer a risky business – and that’s why Brazilian carders have joined forces with local coders to develop an easier, more secure way to steal and clone credit card information. From this unholy alliance, the ‘Chupa Cabra’ malware was born.

Cybercriminals are always looking for new ways to infect systems – ideally without being noticed until it’s too late. The sky is the limit for their creativity, as the latest wave of malicious boot loaders shows. The kit has been pioneered by Brazilian Trojan bankers who aim to remove security software.

This non-traditional infection only affects systems using ntldr, the default boot loader on Windows NT up to and including Windows XP and Windows Server 2003. This choice was no coincidence - XP is still the most popular OS in several countries, including Brazil, where it runs on nearly 47% of all machines.

In the past few days several Brazilian ISPs have fallen victim to a series of DNS cache poisoning attacks. These attacks see users being redirected to install malware before connecting to popular sites. Some incidents have also featured attacks on network devices, where routers or modems are compromised remotely.

Brazil has some big ISPs. Official statistics suggest the country has 73 million computers connected to the Internet, and the major ISPs average 3 or 4 million customers each. If a cybercriminal can change the DNS cache in just one server, the number of potential victims is huge.

Last week Brazil’s web forums were alive with desperate cries for help from users who faced malicious redirections when trying to access websites such as YouTube, Gmail and Hotmail, as well as local market leaders including Uol, Terra and Globo. In all cases, users were asked to run a malicious file as soon as the website opened.

We monitored one attack which saw a clean machine displaying this warning when opening Google:

Brazilian cybercriminals have always been very active in the creation and dissemination of banking Trojans among their compatriots. But now they are redirecting their attacks beyond the borders of Brazil to target banks in Europe. In recent months we have seen several Trojans developed in Brazil attempting to attack financial institutions in Europe, especially in Spain and Portugal.

As a rule, European banks were attacked by sophisticated Trojan bankers like SpyEye and by Zeus gangs, but now they face an onslaught from Brazilian Trojans. Our statistics show the dissemination of a specific variant affecting customers in Brazil and Portugal:

Trojan-Banker.Win32.Banbra.akzy