BLACK FRIDAY: 2-for-1 offer NOVEMBER 20 - 26 See details
8
Global rank
7
Month rank
6
Week rank
1367
IOCs

FormBook is a data stealer that is being distributed as a MaaS. FormBook differs from a lot of competing malware by its extreme ease of use that allows even the unexperienced threat actors to use FormBook virus.

Stealer
Type
Unknown
Origin
1 January, 2016
First seen
2 December, 2023
Last seen
Also known as
Xloader

How to analyze Formbook with ANY.RUN

Type
Unknown
Origin
1 January, 2016
First seen
2 December, 2023
Last seen

IOCs

Hashes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http://www.cetres.cfd/sy11/
http://www.a2zglobalimports.com/kmge/
http://www.interportodiroma.com/ui23/
http://www.shelterinds.com/o11y/
http://www.trsmine.com/ey16/
http://www.goanyq.icu/st58/
http://www.pfannen-scholl.info/mg0g/
http://www.canlitinib.com/mg0g/
http://www.zzennsensual.com/mg0g/
http://www.cealr.link/mg0g/
http://www.alexbruma.com/mg0g/
http://www.shutlleross.life/mg0g/
http://www.prospin.click/mg0g/
http://www.optime19.com/mg0g/
http://www.myvicesweats.com/q0a9/
http://www.book2110.com/q0a9/
http://www.whistle.news/mg0g/
http://www.xbjuh.com/8fka/
http://www.wangbaomen23.xyz/nfgh/
http://www.venitro.com/gy14/
Last Seen at

Recent blog posts

3 Cybersecurity Events ANY.RUN Attended in No...
watchers 140
comments 0
5 malware threats we discovered in the wild i...
watchers 343
comments 0
RisePro Malware Analysis: Exploring C2 Commun...
watchers 2312
comments 0

What is FormBook malware?

FormBook stealer is an infostealer‍ trojan available as a malware-as-service. This malware is often used by attackers with low technical literacy and little programming knowledge. FormBook can be used to steal various information from infected machines.

Despite how easy it is to set up and use, the malware has advanced stealing and evasion functions including the ability to pull stored and recorded user input. In addition, the FormBook stealer is capable of searching for, viewing, and interacting with files, and taking screenshots. Even though the stealing capability of this virus can be considered somewhat average, its ease of operation, the injection schema, and a set of effective measures that the malware takes to avoid detection by antivirus software made FormBook a popular virus in the hacker community and, unfortunately, its popularity is only continuing to rise in 2019.

General description of the FormBook stealer

Written in C and x86 assembly language, FormBook is sold as a PHP control panel and can be purchased on highly accessible online forums for merely 30 dollars.

Uniquely, unlike the majority of existing viruses that exploit the latest vulnerabilities or zero-days, FormBook can inject into processes and set up function hooks utilizing already known issues. Hence the claim made by the makers, that the virus will work flawlessly regardless of the Windows version.

Together with its stealer functionality and evasion techniques, the virus knows how to execute instructions from a control server that includes starting new processes, their injection, and rebooting the victim’s PC. What’s more, the virus is able to record Windows’ ntdll.dll module into memory and call it directly, which makes API monitoring and user-mode hooking almost insufficient.

Use ANY.RUN free for 14 days

Try the full power of interactive analysis

Start your free trial

FormBook malware analysis

A video simulation recorded on the ANY.RUN interactive malware analysis service allows us to take an in-depth look at the behavior of this clever virus and other malware such as Dridex and Lokibot with their elaborate anti-evasion techniques.

formbook execution process graph

Figure 1: Processes created by FormBook during execution as shown by ANY.RUN simulation

  • As shown by the ANY.RUN simulation, firstly the virus established connection to the CnC server;
  • After this, a malicious executable file, in this analysis's case pretending to be a .png is being dropped or overwritten and executed;
  • Then, FormBook proceeds to steal the personal data and change the autorun value in the registry. Also, the virus loads DLL from Mozilla Firefox creates files in the user directory, and starts CMD.EXE to set up persistence and later begin process injection;
  • Finally, injected Firefox.exe is executed for logging keystrokes, stealing clipboard data, and extracting authentication information from browser HTTP sessions.

Distribution of the FormBook stealer

According to FormBook analysis, malware is usually distributed via email campaigns that utilized a wide array of infecting mechanisms and can contain a number of various file attachments. Among the most commonly observed attachments are either PDFs, DOC or EXE, or ZIP, RAR, ACE, and ISO files.

Campaigns in which the virus is distributed through files with PDF extensions are known to utilize shipping-related themes and usually include a download link that points at the malicious code instead of the actual virus. DOC and EXE campaigns utilize macros to install and run the virus. Often, the virus is retrieved as a .PDF file in such a case. Finally, archive campaigns are considered to be the most common attack vector for this virus and usually revolve around a business-related theme, such as a payment order. In the case of this attack vector, attachments either contain a link to the FormBook stealer EXE file or install and run the virus on victims' PCs directly.

In 2020 Formbook has become quite popular as it used Covid-themed emails for decoys with subject headings such as “Government Response to Coronavirus Covid-19”.

FormBook execution process

Sandbox simulation performed on the ANY.RUN interactive malware hunting service allows us to detect and investigate the behavior of FormBook in a lot of detail.

text report of the formbook malware analysis

Figure 2: A text report generated by ANY.RUN

After downloading the malicious file the only thing needed to start the contamination is for the file to be opened. In a case when Microsoft Office file (doc, xls, rtf) is used as an infection source, after it is opened the malware exploits the CVE-2017-11882 vulnerability, thus Microsoft Office Equation Editor proceeds to download a malicious executable file and run it.

After infecting the victim's PC, the virus copies and renames itself into a directory that differs based on the privileges of the user. If an admin account is used, the virus installs itself in either %ProgramFiles% or %CommonProgramFiles%. On the other hand, if the privileges are not elevated, then the virus will copy itself into %TEMP% or %APPDATA.

Also, Formbook trojan changes the autorun value in the registry depending on is it was running with normal or elevated privileges. Next, the malware copies itself into a directory it proceeds to check if it’s being run on a virtual machine or analyzed, evaluating the best anti-evasion option that can be utilized in a particular situation. Meanwhile, the virus will try to evaluate the USERNAME environment variable to find out if it’s launched in simulation, while also checking for the presence of debuggers. It should be noted that the malware uses particularly clever techniques while performing an analysis, for example, all shared strings such as command server names are decoded only briefly if they are absolutely required, which makes FormBook highly elusive. In the next step, the virus uses the same injection method to an active explorer.exe process which is only employed as a non-permanent staging ground.

The virus occasionally performs injections into web browser processes and explorer.exe. After injecting into the process, the virus chooses a random application from a static list. Then, the virus proceeds to run the chosen application in suspended mode and copy itself in the address space of the suspended process, thus mimicking a genuine Microsoft process. Next, the virus exits the original process which leaves FormBook's dead code in explorer.exe as a result. From this stage, new FormBook processes can inject targeted applications like web browser processes, which in the case of this particular ANY.RUN simulation is Firefox.

Depending on the objective process, the virus can establish various function hooks. Being run from inside the context of an already generated process, the virus starts to go through every currently active process, trying to identify targeted programs. As soon as a target is found, FormBook will inject itself into it and install a particular set of API hooks, that are based on the target program. The data is then saved in files in the %APPDATA% directory until it is sent to the C&C server. Pay attention to this function to detect malware.

How to avoid infection by FormBook?

The best counteraction technique is to exhibit caution when receiving emails with attachments from unknown senders. Attackers usually use social engineering to trick victims into downloading and opening infected files.

Deleting any suspicious emails from the inbox is a good way to stay safe. If the infection is already detected, a good practice is to carry out an analysis of all devices connected to the network for established CnC or potentially malicious URL connections. Once a suspicious email is received, perimeter settings can be adjusted to block all related emails in the future. Finally, if an infected file is already downloaded, the host should be quarantined until the threat is completely mitigated.

How to detect Formbook using ANY.RUN?

Formbook trojan usually injects into explorer.exe and another processes from the list, such as firefox.exe and msiexec.exe. Knowing this malware's function you can take a look at the process tree after a while during execution and easily determine either the sample is Formbook or not.

formbook execution process tree Figure 3: A tree of processes created by Formbook during its execution

Conclusion

Thanks to extreme ease of use and low cost, FormBook is gaining traction in the criminal community. Not only is the virus's functionality freely accessible for download on open hacker forums and easy to set up without any programming knowledge, but it also comes equipped with some highly advanced anti-evasion techniques, that make detecting it with anti-virus software ultra-difficult. ANY.RUN interactive malware hunting service enables to study FormBook in detail from a secure environment and implement cybersecurity measures accordingly.

HAVE A LOOK AT

Adwind screenshot
Adwind
adwind trojan
Adwind RAT, sometimes also called Unrecom, Sockrat, Frutas, jRat, and JSocket, is a Malware As A Service Remote Access Trojan that attackers can use to collect information from infected machines. It was one of the most popular RATs in the market in 2015.
Read More
Agent Tesla screenshot
Agent Tesla
agenttesla trojan rat stealer
Agent Tesla is spyware that collects information about the actions of its victims by recording keystrokes and user interactions. It is falsely marketed as a legitimate software on the dedicated website where this malware is sold.
Read More
Amadey screenshot
Amadey
amadey
Amadey is a formidable Windows infostealer threat, characterized by its persistence mechanisms, modular design, and ability to execute various malicious tasks.
Read More
Arkei screenshot
Arkei
arkei stealer
Arkei is a stealer type malware capable of collecting passwords, autosaved forms, cryptocurrency wallet credentials, and files.
Read More
AsyncRAT screenshot
AsyncRAT
asyncrat
AsyncRAT is a RAT that can monitor and remotely control infected systems. This malware was introduced on Github as a legitimate open-source remote administration software, but hackers use it for its many powerful malicious functions.
Read More
WarZone screenshot
WarZone
warzone avemaria stealer trojan rat
WarZone RAT is a remote access trojan, which is written in C++ and offered as a malware-as-a-service. It packs a wide range of capabilities, from stealing victims’ files and passwords to capturing desktop activities. WarZone RAT is primarily distributed via phishing emails and receives regular updates from its C2.
Read More

Our website uses cookies. By visiting the pages of the site, you agree to our Privacy Policy