Malware descriptions

Malware in the cloud

The use of all kind of services in a cloud basis is becoming more and more popular, enhancing productivity and reducing the needs of setting up a complex infrastructure. This approach is progressively being taken by IT industry. However, malware reacted faster in abusing this virtual infrastructure for its profit.

We have seen many examples in the past: the use of Twitter as a communication channel for a botnet, using Amazon EC2 for hosting C&Cs or abusing advertising channels for distributing malware. Today we will see, through a sample, how malware maximizes its revenues using this kind of services with a minimum impact on victims computer.

Our sample belongs to Trojan-Dropper.Win32.Drooptroop family, which has more than 7000 variants. The sample is detected by Kaspersky Internet Security as Trojan-Dropper.Win32.Drooptroop.jpa, and its peak of activity corresponds to 6th of December, mostly based in the US.

It is being distributed through an email message with a link to a Rapidshare file:

hxxp://rapidshare.com/files/4XXXXXXX0/gift.exe

Taking advantage of the Christmas campaign, the name of the binary is gift.exe. As suspicious as it is, however, most filters fail in detecting this as malicious for two reasons: the binary is not in the body message and the domain of the URL is legitimate. We have detected more than 1000 infections were technique was used for distributing the sample.

This is not the only use of external infrastructure done by the sample. Once the computer is infected,Drooptroop.jpa injects code into spoolsv.exe and intercepts browsers network functions, resulting in hijacking users requests.

Doing this, Drooptroop performs click fraud redirecting legitimate requests:

GET
/click.php?c=eNXXXXXSA HTTP/1.1

Host:
64.111.xxx.xxx

User-Agent:
Mozilla/5.0 (Windows; U; Windows NT 5.1; es-ES; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3

Accept:
text/html,applicationxhtml+xml,applicationxml;q=0.9,*/*;q=0.8

Accept-Language:
es-es,es;q=0.8,en-us;q=0.5,en;q=0.3

Accept-Encoding:
gzip,deflate

Accept-Charset:
ISO-8859-1,utf-8;q=0.7,*;q=0.7

Keep-Alive:
115

Connection:
keep-alive

Referer: hxxp://wwwxxx.com/go/beXXXX4

This remuneration programs are abused on a regular basis by malware. Apart from that, this malware redirects the user to rogue AV sites:

It is interesting how everything is shown in the browser. All is javascript highly obfuscated simulating explorer, so further binaries are downloaded to the computer at the scaring phase.

At this point, you probably want to run Kaspersky Internet Security to clean your system.

Summing it up, the distribution was using a remote file sharing service, the malware used click fraud to monetize and the rogue AV was all happening in the browser. However this malware still needed to infect your computer, so dont forget to protect yourself.

Malware in the cloud

Your email address will not be published. Required fields are marked *

 

Reports

Lyceum group reborn

According to older public researches, Lyceum conducted operations against organizations in the energy and telecommunications sectors across the Middle East. In 2021, we have been able to identify a new cluster of the group’s activity, focused on two entities in Tunisia.

GhostEmperor: From ProxyLogon to kernel mode

While investigating a recent rise of attacks against Exchange servers, we noticed a recurring cluster of activity that appeared in several distinct compromised networks. With a long-standing operation, high profile victims, advanced toolset and no affinity to a known threat actor, we decided to dub the cluster GhostEmperor.

APT trends report Q2 2021

This is our latest summary of advanced persistent threat (APT) activity, focusing on significant events that we observed during Q2 2021: attacks against Microsoft Exchange servers, APT29 and APT31 activities, targeting campaigns, etc.

Subscribe to our weekly e-mails

The hottest research right in your inbox