AZORult spreads as a fake ProtonVPN installer – 10 minute mail

AZORult has its history. However, a few days ago, we discovered what appears to be one of its most unusual campaigns: abusing the ProtonVPN service and dropping malware via fake ProtonVPN installers for Windows.

Screenshot of a fake ProtonVPN website

The campaign started at the end of November 2019 when the threat actor behind it registered a new domain under the name protonvpn[.]store. The Registrar used for this campaign is from Russia.

We have found that at least one of the infection vectors is through affiliation banners networks (Malvertising).

When the victim visits a counterfeit website and downloads a fake ProtonVPN installer for Windows, they receive a copy of the Azorult botnet implant.

The Website is an HTTrack copy of the original ProtonVPN website as shown below.

Once the victim runs the implant, it collects the infected machine’s environment information and reports it to the C2, located on the same accounts[.]protonvpn[.]store server.

In their greed, the threat actors have designed the malware to steal cryptocurrency from locally available wallets (Electrum, Bitcoin, Etherium, etc.), FTP logins and passwords from FileZilla, email credentials, information from locally installed browsers (including cookies), credentials for WinSCP, Pidgin messenger and others.

We have been able to identify a few samples associated with the campaign:

Filename MD5 hash
ProtonVPN_win_v1.10.0.exe cc2477cf4d596a88b349257cba3ef356
ProtonVPN_win_v1.11.0.exe 573ff02981a5c70ae6b2594b45aa7caa
ProtonVPN_win_v1.11.0.exe c961a3e3bd646ed0732e867310333978
ProtonVPN_win_v1.11.0.exe 2a98e06c3310309c58fb149a8dc7392c
ProtonVPN_win_v1.11.0.exe f21c21c2fceac5118ebf088653275b4f
ProtonVPN_win_v1.11.0.exe 0ae37532a7bbce03e7686eee49441c41
Unknown 974b6559a6b45067b465050e5002214b

Kaspersky products detect this threat as HEUR:Trojan-PSW.Win32.Azorult.gen


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Mokes and Buerak distributed under the guise of security certificates – 10 minute mail

The technique of distributing malware under the guise of legitimate software updates is not new. As a rule, cybercriminals invite potential victims to install a new version of a browser or Adobe Flash Player. However, we recently discovered a new approach to this well-known method: visitors to infected sites were informed that some kind of security certificate had expired. Unsurprisingly, the update on offer was malicious.

We detected the infection on variously themed websites — from a zoo to a store selling auto parts. The earliest infections found date back to January 16, 2020.

Attack pattern

This is what visitors of any of the hacked websites saw:

The alarming notification consists of an iframe — with contents loaded from the third-party resource ldfidfa[.]pw — overlaid on top of the original page. The URL bar still displays the legitimate address. This is what the malicious piece of code inserted into the original HTML page looks like:

From the screenshot it can be seen that the script parameters depend on the referrer, user_agent, and cookie values of the user. While the following fixed values are used as the user_agent_X and timestamp_X strings:

  • user_agent_X = Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.117 Safari/537.36
  • timestamp_X = 1579118411.0231 (01/15/2020 @ 8:00pm (UTC))

The code inserted by the cybercriminal loads the external malicious script ldfidfa[.]pw/jquery.js?&up= &ts= &r= &u= &c=

Malicious jquery.js script

The jquery.js script overlays an iframe that is exactly the same size as the page. The iframe content is loaded from the address https[:]//ldfidfa[.]pw//chrome.html. As a result, instead of the original page, the user sees a seemingly genuine banner urgently prompting to install a certificate update.

Clicking the Install (Recommended) button on the banner initiates the download of the file Certificate_Update_v02.2020.exe, which we detect as Exploit.Win32.ShellCode.gen. Analysis of the file showed it to be Trojan-Downloader.Win32.Buerak, packed using Nullsoft Scriptable Install System. It is not the only malware distributed by the attackers. For example, Backdoor.Win32.Mokes was spread via the same campaign earlier in January.

IoC

Exploit.Win32.ShellCode.gen
B3290148681F8218ECB80CA430F9FDBA (Certificate_Update_v02.2020.exe)

Trojan-Downloader.Win32.Buerak
CE1931C2EB82B91ADB5A9B9B1064B09F

Backdoor.Win32.Mokes
094ADE4F1BC82D09AD4E1C05513F686D
F869430B3658A2A112FC85A1246F3F9D
5FB9CB00F19EAFBF578AF693767A8754
47C5782560D2FE3B80E0596F3FBA84D3

C&C
kkjjhhdff[.]site (47.245.30[.]255)
oderstrg[.]site


Temp Mails (https://tempemail.co/) is a new free temporary email addresses service. This service provide you random 10 minutes emails addresses. It is also known by names like: temporary mail, disposable mail, throwaway email, one time mail, anonymous email address… All emails received by Tempmail servers are displayed automatically in your online browser inbox.

Mokes and Buerak distributed under the guise of security certificates – 10 minute mail

The technique of distributing malware under the guise of legitimate software updates is not new. As a rule, cybercriminals invite potential victims to install a new version of a browser or Adobe Flash Player. However, we recently discovered a new approach to this well-known method: visitors to infected sites were informed that some kind of security certificate had expired. Unsurprisingly, the update on offer was malicious.

We detected the infection on variously themed websites — from a zoo to a store selling auto parts. The earliest infections found date back to January 16, 2020.

Attack pattern

This is what visitors of any of the hacked websites saw:

The alarming notification consists of an iframe — with contents loaded from the third-party resource ldfidfa[.]pw — overlaid on top of the original page. The URL bar still displays the legitimate address. This is what the malicious piece of code inserted into the original HTML page looks like:

From the screenshot it can be seen that the script parameters depend on the referrer, user_agent, and cookie values of the user. While the following fixed values are used as the user_agent_X and timestamp_X strings:

  • user_agent_X = Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.117 Safari/537.36
  • timestamp_X = 1579118411.0231 (01/15/2020 @ 8:00pm (UTC))

The code inserted by the cybercriminal loads the external malicious script ldfidfa[.]pw/jquery.js?&up= &ts= &r= &u= &c=

Malicious jquery.js script

The jquery.js script overlays an iframe that is exactly the same size as the page. The iframe content is loaded from the address https[:]//ldfidfa[.]pw//chrome.html. As a result, instead of the original page, the user sees a seemingly genuine banner urgently prompting to install a certificate update.

Clicking the Install (Recommended) button on the banner initiates the download of the file Certificate_Update_v02.2020.exe, which we detect as Exploit.Win32.ShellCode.gen. Analysis of the file showed it to be Trojan-Downloader.Win32.Buerak, packed using Nullsoft Scriptable Install System. It is not the only malware distributed by the attackers. For example, Backdoor.Win32.Mokes was spread via the same campaign earlier in January.

IoC

Exploit.Win32.ShellCode.gen
B3290148681F8218ECB80CA430F9FDBA (Certificate_Update_v02.2020.exe)

Trojan-Downloader.Win32.Buerak
CE1931C2EB82B91ADB5A9B9B1064B09F

Backdoor.Win32.Mokes
094ADE4F1BC82D09AD4E1C05513F686D
F869430B3658A2A112FC85A1246F3F9D
5FB9CB00F19EAFBF578AF693767A8754
47C5782560D2FE3B80E0596F3FBA84D3

C&C
kkjjhhdff[.]site (47.245.30[.]255)
oderstrg[.]site


Temp Mails (https://tempemail.co/) is a new free temporary email addresses service. This service provide you random 10 minutes emails addresses. It is also known by names like: temporary mail, disposable mail, throwaway email, one time mail, anonymous email address… All emails received by Tempmail servers are displayed automatically in your online browser inbox.

AZORult spreads as a fake ProtonVPN installer – 10 minute mail

AZORult has its history. However, a few days ago, we discovered what appears to be one of its most unusual campaigns: abusing the ProtonVPN service and dropping malware via fake ProtonVPN installers for Windows.

Screenshot of a fake ProtonVPN website

The campaign started at the end of November 2019 when the threat actor behind it registered a new domain under the name protonvpn[.]store. The Registrar used for this campaign is from Russia.

We have found that at least one of the infection vectors is through affiliation banners networks (Malvertising).

When the victim visits a counterfeit website and downloads a fake ProtonVPN installer for Windows, they receive a copy of the Azorult botnet implant.

The Website is an HTTrack copy of the original ProtonVPN website as shown below.

Once the victim runs the implant, it collects the infected machine’s environment information and reports it to the C2, located on the same accounts[.]protonvpn[.]store server.

In their greed, the threat actors have designed the malware to steal cryptocurrency from locally available wallets (Electrum, Bitcoin, Etherium, etc.), FTP logins and passwords from FileZilla, email credentials, information from locally installed browsers (including cookies), credentials for WinSCP, Pidgin messenger and others.

We have been able to identify a few samples associated with the campaign:

Filename MD5 hash
ProtonVPN_win_v1.10.0.exe cc2477cf4d596a88b349257cba3ef356
ProtonVPN_win_v1.11.0.exe 573ff02981a5c70ae6b2594b45aa7caa
ProtonVPN_win_v1.11.0.exe c961a3e3bd646ed0732e867310333978
ProtonVPN_win_v1.11.0.exe 2a98e06c3310309c58fb149a8dc7392c
ProtonVPN_win_v1.11.0.exe f21c21c2fceac5118ebf088653275b4f
ProtonVPN_win_v1.11.0.exe 0ae37532a7bbce03e7686eee49441c41
Unknown 974b6559a6b45067b465050e5002214b

Kaspersky products detect this threat as HEUR:Trojan-PSW.Win32.Azorult.gen


Temp Mails (https://tempemail.co/) is a new free temporary email addresses service. This service provide you random 10 minutes emails addresses. It is also known by names like: temporary mail, disposable mail, throwaway email, one time mail, anonymous email address… All emails received by Tempmail servers are displayed automatically in your online browser inbox.