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Peter Coogan | November 4th, 2009
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The Fragus exploit pack showed up on our radar a few months ago and has been steadily growing to become one of the most prevalent exploit packs being seen in the wild today by Symantec. It is similar to other popular exploit packs available—such as Unique, YES, Eleonore, and Liberty—but it brings some new and interesting features with it. Exploit packages are generally designed as a means to allow attackers to group and serve exploits from their website against the browsers of unsuspecting visitors. It is done in a nice GUI form, hosted on a Web server, and allows the attacker to generally choose which exploits to run. Once exploited, a final payload is served to the system. All of this is dished up in a control panel with some nice statistics on how successful the campaign has been.  

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Ben Nahorney | November 3rd, 2009
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Threats targeting the Macintosh platform are much less common than those targeting Windows. The same can be said about video games, where Windows is the dominate platform of the two. Combining games and malware has happened before, but a Mac game performing malicious activities? That’s something relatively new.

Takashi Katsuki, one of our Tokyo engineers, came across just that today. The game looks to be a throw-back to the classic Space Invaders/Galaga style of games from the early 1980s. However, what brings this game into the realm of malicious code is that for every alien ship you destroy, the game deletes a file from your home directory.

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Mayur Kulkarni | November 3rd, 2009
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Symantec recently reported a malicious spam campaign against Facebook, which is now accompanied by a phishing attack. These messages look like an official Facebook invite or password reset confirmation mail.

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If we place the cursor over the update button in the message, we can actually see the phishing URL in the status bar. If a user clicks on the “Update” button, he or she is redirected to a Facebook look-alike phishing site. Here, users are asked to enter a password to complete the update procedure. Unfortunately, the user’s password will be stolen if they try to log in on this page.

These attacks can be identified by the subject lines listed below:

Facebook account update
New login system
Facebook Update tool

In...

Andrea Lelli | October 31st, 2009
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Sure we have heard a lot about bots and botnets. One key component of a botnet is the command-and-control (C&C) server, which as we know can come in several flavours (IRC, Web pages, newsgroups, custom servers, etc.). Yet, here comes Trojan.Whitewell, which, being tired of old C&C channels, decides to pick up Facebook as a coordinator for the C&C server. I use the word “coordinator” because the Trojan only receives some configuration data from its Facebook account—the actual command execution and data reporting is done through a third party Web server.

The Trojan was sent through a popular malware distribution channel that is also related to other prevalent threats such as Trojan.Bredolab. The distribution technique is pretty simple: they send documents (PDF, or MS Office formats) containing exploits for known vulnerabilities. These documents usually...

Shunichi Imano | October 29th, 2009
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Symantec Security Response has become aware of a Trojan Horse we detect as Trojan.Ramvicrype. The Trojan uses the RC4 algorithm to encrypt files on compromised computers, rendering them unusable. Presence of files with a .vicrypt extension is a sure-fire sign of infection.

Trojan.Ramvicrype is a little different from most other Ransomware programs we’ve seen in the past. Typically these kinds of threats display a message prompting users to visit a certain Web page or email a specific address. Users will end up paying the online criminals in exchange for keys that can be used to unlock the computer or decrypt the encrypted files.

Previously posted blogs on the subject of Ransomware can be found at:

Patrick Fitzgerald | October 29th, 2009
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While looking through some recent customer submissions a particular filename caught my attention. It was called “googlewaveinvitegenerator.exe”. Google Wave is a new communication application being developed by Google. Many people who missed the initial sign up for this application are now seeking invites to the service. Certain bad guys have latched onto this and are attempting to take advantage of the situation to push malware. In this case the malware in question is Backdoor.Tidserv. It’s also worth pointing out Google Wave was only selected because of its current popularity. Using a trusted brand like this also increases the chance of success for the attacker. This technique is something we see all of the time.

This particular campaign tries to trick people who want to get into the Google Wave community by promising not only an application that generates Google Wave invites, but also untold riches by selling these invites to other people who want to...

Shunichi Imano | October 27th, 2009
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Security Response is aware of a new round of spam replacing old DHL and UPS themes in an attempt to spread Trojan.Bredolab.

Taking a Closer Look at Trojan.Bredolab
Bredolab Delivers More Parcels and Cash
 

This time the email is masquerading as a notification from Facebook that the recipient’s password has been reset.

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The message comes with a .zip file containing a malicious .exe file. Symantec detects the .exe files as Trojan.Bredolab.

This...
Nicolas Falliere | October 26th, 2009
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Clampi goes to unusual measures to bypass the local firewall on the compromised computer, such as the Windows Firewall. Usually, such firewalls allow only specific programs to communicate using specific ports and protocols. For instance, your browser would be allowed to use outbound TCP port 80.

As we’ve previously discussed, Clampi needs to communicate with a “Gate” gateway server in order to get its orders and send information. Any firewall would block the program if it tried to connect to the outside world. Bypassing this can be done in many ways, the most common one in the malware world being to add an entry in the Windows registry, added the program to the trusted file list.

The Clampi gang decided to inject their networking code into Internet Explorer, which is granted Web access by any standard firewall configuration out there. Fair enough—that’s another approach, but not a new one. Yet you’ve seen these guys don’t do...

Nicolas Falliere | October 23rd, 2009
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Today, we’ll discuss the two remaining Clampi modules used for replication and traffic relay capabilities. The SOCKS module is very straight-forward—it’s a SOCKS proxy server. Normal SOCKS proxy servers act as a connection relays and are used for many purposes, such as connection filtering, passing traffic through firewalls, or to maintain anonymity.

The server’s code is injected into an instance of Internet Explorer. It then listens for incoming connections on a random TCP port above 5000. The SOCKS module is activated in response to a control server’s command. The client then sends the port it’s listening on for inbound connections to the proxy server:

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In the above example, the SOCKS server will be listening to port 38329 (which is 0x95B9 in hexadecimal base).

Usually, relay servers like...

Nicolas Falliere | October 20th, 2009
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This chapter in our Clampi saga brings us back to the malware’s logging facility. As we saw before, one of Clampi’s modules, codenamed LOGGER, is responsible for logging outgoing information going to a determined list of URLs – stored in a data file as CRCs.

One problem arises with banking sites that preprocess the user’s personal information before sending it over HTTPS—it’s done using client-side JavaScript.  For instance, a hash of the input PIN number could be sent instead of the PIN number itself. This mechanism adds an extra layer of security, preventing malware from sniffing network traffic at one end of the SSL tunnel. But still, it’s only covering one end. It’s more secure than no encryption, but still not great. At least two methods exist to get around this:

  • Setting up a keylogger using either software (...
Nicolas Falliere | October 16th, 2009
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Let’s continue our Trojan.Clampi blog series by discussing three more modules downloaded and executed by Clampi. These modules share the common goal of gathering information, private or not, contained on the compromised computer. They don’t intercept network traffic like the Logger module does (described in my previous blog).

The PROT module
This module gathers private information from several sources, including Protected Storage (PStore), which contains user credentials stored by Internet Explorer or Outlook for instance. Interestingly, it also sets specific registry values in order to facilitate the creation of new entries in the PStore.
For instance, it sets the following registry entires:

  • HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\ “...
Hon Lau | October 14th, 2009
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Over the past few days a sustained email spam campaign has been running to distribute new Zeusbot variants. Initially the campaign kicked off with a story from “your administrator” about some server upgrade that requires you to download and execute a patch to ensure that your computer continues to work properly:
 
Subject: Important - Read Carefully
Email Body:
Attention!

On October 16, 2009 server upgrade will take place. Due to this the system may be offline for approximately half an hour.
The changes will concern security, reliability and performance of mail service and the system as a whole.
For compatibility of your browsers and mail clients with upgraded server software you should run SSl certificates update procedure.

This procedure is quite simple. All you have to do is just to click the link provided, to save the patch file
and then to run it from your computer...

Gilou Tenebro | October 14th, 2009
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Trojan.Bredolab is a threat that has been distributed widely and consistently this year. This research paper takes a closer look at the Trojan to discover how it works, why it’s so widespread, and the motivations behind it.

In short, Bredolab is distributed by spam emails and drive-by-download attacks. (In fact, last month we blogged about a wave of spam emails used to distribute it.) Once it’s on a computer, Bredolab downloads and installs a variety of other threats. This process is outlined in the following diagram.
 
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We have seen Bredolab downloading password stealers, bots, rootkits, backdoors,...

Symantec Security Response | October 13th, 2009
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Malware authors often leave hidden messages in files for analysts to find or for other malware authors to see. However, finding a curse on my whole family in a flash exploit file came as somewhat of a surprise!

The file in question was being distributed on the Internet circa June of this year and was being hosted on some Chinese domains. After decompressing the file and extracting the ActionScript I saw some Chinese characters used within the script. I don’t speak Chinese myself, so I had one of our engineers who does translate the message:

Warning.jpg
 
This roughly translates to:

“Dadong declares that: This file is used only for internal technical research, if you decrypt it your whole family will die, if you use it as a part of a Trojan your whole family will die also! If you use this file illegally you take...

Nicolas Falliere | October 12th, 2009
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As mentioned in our previous blog entry, most of the Trojan.Clampi features reside in separate modules that are sent by a remote server in response to clients’ queries. In this part of this blog series, we’ll have a look at one of the modules used by the malware to steal login credentials mostly from banking Web sites.
 
This module is codenamed LOGGER by the threat. After decryption, the beginning of the module’s raw data looks like this (compressed):

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To avoid downloading the module each time Clampi runs, it is stored in the registry (in an encrypted form) in a value named “Mxx”, where “xx” is a zero-based number...