In 2024, Arete’s Incident Response (IR) team responded to dozens of incidents attributed to the RansomHub threat actor group. Engagements attributed to RansomHub increased rapidly since Arete first observed them in May 2024, and the group quickly established itself as one of the top three threat actor groups since July 2024.
RansomHub has impacted multiple sectors across Arete engagements, including professional services, public services, healthcare, high technology, financial services, and manufacturing. The group has targeted several high-profile targets since its emergence, including telecom giant Frontier and British auction house Christie’s. RansomHub also claimed to possess data stolen from Change Healthcare, which was the victim of an ALPHV/BlackCat ransomware attack in February 2024. RansomHub announced the sale of Change’s data after leaking some of the alleged data a day beforehand.
Advertisements for the RansomHub Ransomware-as-a-Service (RaaS) appeared on cybercriminal forums on February 2, 2024, highlighting an encryptor developed using the C++ and Go programming languages. The use of Go makes it easier for ransomware groups to target a wide variety of operating systems without needing to rewrite significant portions of the malware, as Go allows developers to compile executables for Windows, Linux, and macOS platforms from a single codebase. These advertisements were accompanied by a new data leak site (DLS) under the RansomHub branding on the dark web.
RansomHub is suspected to be a re-brand of the “Knight” ransomware group, whose source code was listed for sale on the underground RAMP forum on February 18, 2024. From research, Arete can confirm various similarities between RansomHub and Knight’s encryptors.
This spotlight explores the ransomware group’s observed behavior, background information on the threat actor, and statistics from Incident Response engagements, along with a technical analysis of RansomHub’s ransomware executable. Finally, we discuss security recommendations to better defend against this evolving cyber threat and mitigate the risk of financial and reputational losses.
Incident Response Data on the RansomHub Ransomware Group
The information provided below is based on engagements involving the RansomHub threat actor groupinvestigated by Aretein2024.Our IR,Threat Intelligence,and Data Analytics teams work togetherto analyze key data points during every ransomware engagement and form real-timethreat actor(TA)insights.
- Targeted sectors include professional services,public services,healthcare,high technology,financial services,and manufacturing.
- The median initial ransom demand is $900,000.
- The median ransom payment facilitated is $350,000.
- Tools and malware observed during investigations include SocGholish,CobaltStrike,Mimikatz,Rclone,Filezilla,WinSCP,PsExec,AnyDesk,PuTTY,WinSCP,Rclone,SoftPerfect Network Scanner,and TDSSKiller and EDRKillShifter to disable EDR software to evade detection.
- RansomHub-affiliated actors have exploited vulnerabilitiesina variety of technologies,including Apache ActiveMQ,Atlassian Confluence,Citrix ADC,F5 BIG-IP,and Fortinet FortiOS.
- The group operates a data leak site(DLS)self-proclaimedas “RansomHub” and commonly threatensvictims withreleasing stolen dataas a pressure tactic ifa payment is not made.
- The file extension appended to encrypted files is created based on the first six characters ofthe Curve 25519public key,and files are encrypted using a decrypted Curve 25519public key andAES algorithms.
- The ransom note created self-identifies the groupas RansomHub and references their data leakand chat negotiation sites. Thefilename of the ransom note is dependent on the encrypted fileextensionas a naming convention and follows this format:“README_.txt”. For example:README_11f5ew.txt.
- In addition to encrypting files and creating a ransom note,the RansomHub ransomware needs apassword to properly execute,supports various command line arguments,deletes volume shadowcopies,clears the Windows Event Logs,and tries to stop virtual machines(VMs)
The information provided below is based on engagements involving the RansomHub threat actor groupinvestigated by Aretein2024.Our IR,Threat Intelligence,and Data Analytics teams work togetherto analyze key data points during every ransomware engagement and form real-timethreat actor(TA)insights.
- Targeted sectors include professional services,public services,healthcare,high technology,financial services,and manufacturing.
- The median initial ransom demand is $900,000.
- The median ransom payment facilitated is $350,000.
- Tools and malware observed during investigations include SocGholish,CobaltStrike,Mimikatz,Rclone,Filezilla,WinSCP,PsExec,AnyDesk,PuTTY,WinSCP,Rclone,SoftPerfect Network Scanner,and TDSSKiller and EDRKillShifter to disable EDR software to evade detection.
- RansomHub-affiliated actors have exploited vulnerabilitiesina variety of technologies,including Apache ActiveMQ,Atlassian Confluence,Citrix ADC,F5 BIG-IP,and Fortinet FortiOS.
- The group operates a data leak site(DLS)self-proclaimedas “RansomHub” and commonly threatensvictims withreleasing stolen dataas a pressure tactic ifa payment is not made.
- The file extension appended to encrypted files is created based on the first six characters ofthe Curve 25519public key,and files are encrypted using a decrypted Curve 25519public key andAES algorithms.
- The ransom note created self-identifies the groupas RansomHub and references their data leakand chat negotiation sites. Thefilename of the ransom note is dependent on the encrypted fileextensionas a naming convention and follows this format:“README_.txt”. For example:README_11f5ew.txt.
- In addition to encrypting files and creating a ransom note,the RansomHub ransomware needs apassword to properly execute,supports various command line arguments,deletes volume shadowcopies,clears the Windows Event Logs,and tries to stop virtual machines(VMs)
The information provided below is based on engagements involving the RansomHub threat actor groupinvestigated by Aretein2024.Our IR,Threat Intelligence,and Data Analytics teams work togetherto analyze key data points during every ransomware engagement and form real-timethreat actor(TA)insights.
- Targeted sectors include professional services,public services,healthcare,high technology,financial services,and manufacturing.
- The median initial ransom demand is $900,000.
- The median ransom payment facilitated is $350,000.
- Tools and malware observed during investigations include SocGholish,CobaltStrike,Mimikatz,Rclone,Filezilla,WinSCP,PsExec,AnyDesk,PuTTY,WinSCP,Rclone,SoftPerfect Network Scanner,and TDSSKiller and EDRKillShifter to disable EDR software to evade detection.
- RansomHub-affiliated actors have exploited vulnerabilitiesina variety of technologies,including Apache ActiveMQ,Atlassian Confluence,Citrix ADC,F5 BIG-IP,and Fortinet FortiOS.
- The group operates a data leak site(DLS)self-proclaimedas “RansomHub” and commonly threatensvictims withreleasing stolen dataas a pressure tactic ifa payment is not made.
- The file extension appended to encrypted files is created based on the first six characters ofthe Curve 25519public key,and files are encrypted using a decrypted Curve 25519public key andAES algorithms.
- The ransom note created self-identifies the groupas RansomHub and references their data leakand chat negotiation sites. Thefilename of the ransom note is dependent on the encrypted fileextensionas a naming convention and follows this format:“README_.txt”. For example:README_11f5ew.txt.
- In addition to encrypting files and creating a ransom note,the RansomHub ransomware needs apassword to properly execute,supports various command line arguments,deletes volume shadowcopies,clears the Windows Event Logs,and tries to stop virtual machines(VMs)
Background
RansomHub became a notable ransomware operation in 2024, and, alongside Akira, represented a verysignificant percentage of Arete Incident Response engagements in Q3 of 2024.
Source: Arete's Q3 2024 Crimeware Report
The group utilizes both Windows and Linux variants of encryptors, which increases its operational capability to target a wide range of victims of various sectors and sizes. RansomHub operates under a double extortion model, which involves exfiltrating sensitive data and encrypting the victims’ systems to coerce a payment for a decryptor and data deletion.
Technical Analysis
Malware analysis revealed that RansomHub ransomware:
Supports multiple command-line arguments.
Requires a password to properly execute and encrypt files.
Encrypts files on the system and mounted shares.
Creates a ransom note with the following filename: .README_.txt
Self-identifies the group as RansomHub in the ransom note.
References a data leak site in the ransom note that, when accessed, self-identifies the group as RansomHub.
Kills a list of processes and services.
Maintains a list of whitelisted files and directories to make sure it will not render the system unusable, preventing recovery when running a decryptor.
Attempts to prevent system recovery by deleting the system’s volume shadow copies.
Clears the Windows event logs.
Creates a desktop wallpaper image in the “%temp%\” directory and later modifies a registry key to change desktop wallpaper.
Execution Pattern/Arguments
The RansomHub ransomware needs command line arguments to execute and encrypt files in the system.
Command line arguments supported:
Command line arguments
Description
-cmd
CMD to be executed before encryption.
-disable-net
Disable network before running.
-fast value
Fast encryption mode.
-file value
Only process file inside defined files. For example, -file C://1.txt, -file D://2.txt.
-host value
Only process net share inside defined hosts. -host 10.10.10.10 -host 10.10.10.11.
-only-local
Only encrypt local disks.
-pass [SHA256 string]
Password needed to execute the ransomware. A 64-character string.
-path value
Only process files inside defined paths. -path C:// -path D:// -path //10.10.10.10/d/
-safeboot
Reboot in Safe Mode before running.
-safeboot-instance
Run as Safe Mode instance.
-skip-vm value
Skip shutting down VMs. Example: -skip-vm “Ubuntu 22.04 LTS”, -skip-vm “Windows Server 2012”.
-sleep [integer value]
Sleep for a period of time to run (minute).
-verbose
Log to console.
Ransomware execution with the command line argument –help:
Figure 1. Command line arguments supported by the ransomware
The ransomware will not execute in the system without the “-pass” argument followed by a SHA-256 value that is unique in each engagement. Execution of ransomware to encrypt files:
Windows operating systems contain features that can help fix corrupted system files, including shadow copies, which are backups of files created by the Volume Shadow Copy Service (VSS). By deleting shadow copies, the ransomware can prevent victims from restoring files from backups, making it more difficult for them to recover their data without paying the ransom.
The ransomware deletes volume shadow copies before file encryption by starting the following process:
The ransomware can enumerate network-mounted shares by scanning the network interfaces.
Data Encrypted for Impact
The ransomware initially finds available drives, then loads the files one by one using the Windows API “FindFirstFileW“ and “FindNextFileW”. The ransomware generates random keys to encrypt the files, and after encrypting them, the keys are encrypted using a public key. To encrypt files, the ransomware uses a combination of a decrypted Curve 25519 public key and AES algorithms.
The default extension value is the first six characters of the Curve 25519 public key.
Figure 2. Extension added to the encrypted files
Files smaller than 0x100000 bytes are completely encrypted. If the file size is larger than 0x100000 bytes, the ransomware encrypts the file in 0x100000 bytes blocks and skips every 0x200000 bytes of data in between encrypted chunks.
Figure 3. 0x100000 bytes encrypted file.
Upon successful execution, the ransomware creates ransom notes with the file name “README_[encrypted_file_extension].txt”
Figure 4. RansomHub ransom note
Ransom note content:
We are the RansomHub.
Your company Servers are locked and Data has been taken to our servers. This is serious.
Good news: – your server system and data will be restored by our Decryption Tool, we support trial decryption to prove that your files can be decrypted; – for now, your data is secured and safely stored on our server; – nobody in the world is aware about the data leak from your company except you and RansomHub team; – we provide free trial decryption for files smaller than 1MB. If anyone claims they can decrypt our files, you can ask them to try to decrypt a file larger than 1MB.
FAQs: Who we are? – Normal Browser Links: https://ransomxifxwc5eteopdobynonjctkxxvap77yqifu2emfbecgbqdw6qd[.]onion.ly/ – Tor Browser Links: http://ransomxifxwc5eteopdobynonjctkxxvap77yqifu2emfbecgbqdw6qd[.]onion/
Want to go to authorities for protection? – Seeking their help will only make the situation worse,They will try to prevent you from negotiating with us, because the negotiations will make them look incompetent,After the incident report is handed over to the government department, you will be fined <This will be a huge amount,Read more about the GDRP legislation: https://en.wikipedia.org/wiki/General_Data_Protection_Regulation>, The government uses your fine to reward them.And you will not get anything, and except you and your company, the rest of the people will forget what happened!!!!!
Think you can handle it without us by decrypting your servers and data using some IT Solution from third-party “specialists”? – they will only make significant damage to all of your data; every encrypted file will be corrupted forever. Only our Decryption Tool will make decryption guaranteed;
Don’t go to recovery companies, they are essentially just middlemen who will make money off you and cheat you. – We are well aware of cases where recovery companies tell you that the ransom price is 5 million dollars, but in fact they secretly negotiate with us for 1 million dollars, so they earn 4 million dollars from you. If you approached us directly without intermediaries you would pay 5 times less, that is 1 million dollars.
Think your partner IT Recovery Company will do files restoration? – no they will not do restoration, only take 3-4 weeks for nothing; besides all of your data is on our servers and we can publish it at any time; as well as send the info about the data breach from your company servers to your key partners and clients, competitors, media and youtubers, etc. Those actions from our side towards your company will have irreversible negative consequences for your business reputation.
You don’t care in any case, because you just don’t want to pay? – We will make you business stop forever by using all of our experience to make your partners, clients, employees and whoever cooperates with your company change their minds by having no choice but to stay away from your company. As a result, in midterm you will have to close your business.
So lets get straight to the point.
What do we offer in exchange on your payment: – decryption and restoration of all your systems and data within 24 hours with guarantee; – never inform anyone about the data breach out from your company; – after data decryption and system restoration, we will delete all of your data from our servers forever; – provide valuable advising on your company IT protection so no one can attack your again.
Now, in order to start negotiations, you need to do the following: – install and run ‘Tor Browser’ from https://www.torproject.org/download/ – use ‘Tor Browser’ open <TA_URL_removed_by_analyst>.onion/ – enter your Client ID: <ID_removed_by_analyst> * do not leak your ID or you will be banned and will never be able to decrypt your files.
There will be no bad news for your company after successful negotiations for both sides. But there will be plenty of those bad news if case of failed negotiations, so don’t think about how to avoid it. Just focus on negotiations, payment and decryption to make all of your problems solved by our specialists within 1 day after payment received: servers and data restored, everything will work good as new.
************************************************
Modify Registry
The ransomware performs a registry key modification to change the desktop wallpaper.
Wallpaper image content from the C:\Users\%USERNAME%\AppData\Local\Temp\MkgXoB.png file:
Mutex
The mutex is the fundamental tool for managing shared resources between multiple threads or processes. Typically, ransomware uses a mutex to avoid reinfecting the victim system and causing multiple layers of encryption. The ransomware did not create a mutex during execution.
Network Activity
The ransomware did not try to communicate with a remote server other than encrypting data from mounted shares.
Indicator Removal
The ransomware clears Windows Event Logs to hide its malicious activity. Windows Event Logs keep a record of a computer’s alerts and notifications. The ransomware runs the following commands to clear the logs:
The ransomware uses the fsutil tool to redirect file system access to a different location after gaining access to a compromised network. The ransomware uses the following command line to redirect file system access, enabling remote to remote and remote to local symbolic links:
fsutil behavior set SymlinkEvaluation R2L:1 fsutil behavior set SymlinkEvaluation R2R:1
RansomHub decrypted configuration information extracted:
{"master_public_key":<public_key_removed_by_analyst> "extension":
"<extension_removed_by_analyst>" "note_file_name":
"README_<extension_removed_by_analyst>.txt", "note_full_text": "We are the RansomHub.
\n\nYour company Servers are locked and Data has been taken to our servers. This is serious.
\n\nGood news:\n- your server system and data will be restored by our Decryption Tool, we supply
trial decryption to prove that your files can be decrypted;\n- for now, your data is secured and
safely stored on our server;\n- nobody in the world is aware about the data leak from your company
except you and RansomHub team;\n- we provide free trial decryption for files smaller than 1MB. If
anyone claims they can decrypt our files, you can ask them to try to decrypt a file larger than
1MB.\n\nFAQs:\nWho we are?\n- Normal Browser Links: https://ransomxifxwc5eteopdobynonjctkxvap77yqifu2emfbecbqdw6qd.onion.ly/\n-
Tor Browser
Links:
http://ransomxifxwc5eteopdobynonjctkxvap77yqifu2emfbecbqdw6qd.onion/\n\nWant to go to authorities
for protection?\n- Seeking their help will only make the situation worse,They will try to prevent
you from negotiating with us, because the negotiations will make them look incompetent,After the
incident report is handed over to the government department, you will be fined
<Thiswillbeahugeamount,Read more about the GDRP legislation:https://
en.wikipedia.org/wiki/General_Data_Protection_Regulation> The government uses your fine to reward
them.And you will not get anything, and except you and your company, the rest of the people will
forget what happened!!!!!\n\nThink you can handle it without us by decrypting your servers and
data using some IT Solution from third-party \"specialists\"?\n- they will only make significant
damage to all of your data; every encrypted file will be corrupted forever. Only our Decryption
Tool will make decryption guaranteed;\nDon't go to recovery companies, they are essentially just
middlemen who will make money off you and cheat you. \n- We are well aware of cases where recovery
companies tell you that the ransom price is 5 million dollars, but in fact they secretly negotiate
with us for 1 million dollars, so they earn 4 million dollars from you. If you approached us
directly without intermediaries you would pay 5 times less, that is 1 million dollars.\n\nThink
your partner IT Recovery Company will do files restoration?\n- no they will not do restoration,
only take 3-4 weeks for nothing; besides all of your data is on our server and we can publish it
at any time; \n as well as send the info about the data breach from your company servers to your
key partners and clients, competitors, media and youtubers, etc. \n Those actions from our side
towards your company will have irreversible negative consequences for your business reputation.
\n\nYou don't care in any case, because you just don't want to pay? \n- We will make you business
stop forever by using all of our experience to make your partners, clients, employees and whoever
cooperates with your company change their minds by having no choice but to stay away from your
company. \nAs a result, in midterm you will have to close your business. \n\nSo lets get straight
to the point.\n\nWhat do we offer in exchange on your payment:\n- decryption and restoration of all
your systems and data within 24 hours with guarantee;\n- never inform anyone about the data breach
out from your company;\n- after data decryption and system restoration, we will delete all of your
data from our servers forever;\n- provide valuable advising on your company IT protection so no
one can hack you again.\n\nNow, in order to start negotiations, you need to do the following:\n-
install and run 'Tor Browser' from https://www.torproject.org/download/\n- use 'Tor Browser'
open <TA_URL_removed_by_analyst> \n- enter your ID or you will be banned and will never be able to
decrypt your files.\n\nThere will be live chat for your company after successful negotiations for
both sides. But there will be plenty of those bad cases of failed negotiations, so don't think about
how to avoid it.\nJust focus on negotiations, payment and describe to make all of your problems
solved by our specialists within 1 day after payment received: servers and data restored,
everything will work good as new.\n\n************************************************\n",
"note_short_text": "Your data is stolen and encrypted, see README_<extension_removed_by_analyst>.txt.", "settings":
{"local_disks"
{"master_public_key":<public_key_removed_by_analyst> "extension":
"<extension_removed_by_analyst>" "note_file_name":
"README_<extension_removed_by_analyst>.txt", "note_full_text": "We are the RansomHub.
\n\nYour company Servers are locked and Data has been taken to our servers. This is serious.
\n\nGood news:\n- your server system and data will be restored by our Decryption Tool, we supply
trial decryption to prove that your files can be decrypted;\n- for now, your data is secured and
safely stored on our server;\n- nobody in the world is aware about the data leak from your company
except you and RansomHub team;\n- we provide free trial decryption for files smaller than 1MB. If
anyone claims they can decrypt our files, you can ask them to try to decrypt a file larger than
1MB.\n\nFAQs:\nWho we are?\n- Normal Browser Links: https://ransomxifxwc5eteopdobynonjctkxvap77yqifu2emfbecbqdw6qd.onion.ly/\n-
Tor Browser
Links:
http://ransomxifxwc5eteopdobynonjctkxvap77yqifu2emfbecbqdw6qd.onion/\n\nWant to go to authorities
for protection?\n- Seeking their help will only make the situation worse,They will try to prevent
you from negotiating with us, because the negotiations will make them look incompetent,After the
incident report is handed over to the government department, you will be fined
<Thiswillbeahugeamount,Read more about the GDRP legislation:https://
en.wikipedia.org/wiki/General_Data_Protection_Regulation> The government uses your fine to reward
them.And you will not get anything, and except you and your company, the rest of the people will
forget what happened!!!!!\n\nThink you can handle it without us by decrypting your servers and
data using some IT Solution from third-party \"specialists\"?\n- they will only make significant
damage to all of your data; every encrypted file will be corrupted forever. Only our Decryption
Tool will make decryption guaranteed;\nDon't go to recovery companies, they are essentially just
middlemen who will make money off you and cheat you. \n- We are well aware of cases where recovery
companies tell you that the ransom price is 5 million dollars, but in fact they secretly negotiate
with us for 1 million dollars, so they earn 4 million dollars from you. If you approached us
directly without intermediaries you would pay 5 times less, that is 1 million dollars.\n\nThink
your partner IT Recovery Company will do files restoration?\n- no they will not do restoration,
only take 3-4 weeks for nothing; besides all of your data is on our server and we can publish it
at any time; \n as well as send the info about the data breach from your company servers to your
key partners and clients, competitors, media and youtubers, etc. \n Those actions from our side
towards your company will have irreversible negative consequences for your business reputation.
\n\nYou don't care in any case, because you just don't want to pay? \n- We will make you business
stop forever by using all of our experience to make your partners, clients, employees and whoever
cooperates with your company change their minds by having no choice but to stay away from your
company. \nAs a result, in midterm you will have to close your business. \n\nSo lets get straight
to the point.\n\nWhat do we offer in exchange on your payment:\n- decryption and restoration of all
your systems and data within 24 hours with guarantee;\n- never inform anyone about the data breach
out from your company;\n- after data decryption and system restoration, we will delete all of your
data from our servers forever;\n- provide valuable advising on your company IT protection so no
one can hack you again.\n\nNow, in order to start negotiations, you need to do the following:\n-
install and run 'Tor Browser' from https://www.torproject.org/download/\n- use 'Tor Browser'
open <TA_URL_removed_by_analyst> \n- enter your ID or you will be banned and will never be able to
decrypt your files.\n\nThere will be live chat for your company after successful negotiations for
both sides. But there will be plenty of those bad cases of failed negotiations, so don't think about
how to avoid it.\nJust focus on negotiations, payment and describe to make all of your problems
solved by our specialists within 1 day after payment received: servers and data restored,
everything will work good as new.\n\n************************************************\n",
"note_short_text": "Your data is stolen and encrypted, see README_<extension_removed_by_analyst>.txt.", "settings":
{"local_disks"
{"master_public_key":<public_key_removed_by_analyst> "extension":
"<extension_removed_by_analyst>" "note_file_name":
"README_<extension_removed_by_analyst>.txt", "note_full_text": "We are the RansomHub.
\n\nYour company Servers are locked and Data has been taken to our servers. This is serious.
\n\nGood news:\n- your server system and data will be restored by our Decryption Tool, we supply
trial decryption to prove that your files can be decrypted;\n- for now, your data is secured and
safely stored on our server;\n- nobody in the world is aware about the data leak from your company
except you and RansomHub team;\n- we provide free trial decryption for files smaller than 1MB. If
anyone claims they can decrypt our files, you can ask them to try to decrypt a file larger than
1MB.\n\nFAQs:\nWho we are?\n- Normal Browser Links: https://ransomxifxwc5eteopdobynonjctkxvap77yqifu2emfbecbqdw6qd.onion.ly/\n-
Tor Browser
Links:
http://ransomxifxwc5eteopdobynonjctkxvap77yqifu2emfbecbqdw6qd.onion/\n\nWant to go to authorities
for protection?\n- Seeking their help will only make the situation worse,They will try to prevent
you from negotiating with us, because the negotiations will make them look incompetent,After the
incident report is handed over to the government department, you will be fined
<Thiswillbeahugeamount,Read more about the GDRP legislation:https://
en.wikipedia.org/wiki/General_Data_Protection_Regulation> The government uses your fine to reward
them.And you will not get anything, and except you and your company, the rest of the people will
forget what happened!!!!!\n\nThink you can handle it without us by decrypting your servers and
data using some IT Solution from third-party \"specialists\"?\n- they will only make significant
damage to all of your data; every encrypted file will be corrupted forever. Only our Decryption
Tool will make decryption guaranteed;\nDon't go to recovery companies, they are essentially just
middlemen who will make money off you and cheat you. \n- We are well aware of cases where recovery
companies tell you that the ransom price is 5 million dollars, but in fact they secretly negotiate
with us for 1 million dollars, so they earn 4 million dollars from you. If you approached us
directly without intermediaries you would pay 5 times less, that is 1 million dollars.\n\nThink
your partner IT Recovery Company will do files restoration?\n- no they will not do restoration,
only take 3-4 weeks for nothing; besides all of your data is on our server and we can publish it
at any time; \n as well as send the info about the data breach from your company servers to your
key partners and clients, competitors, media and youtubers, etc. \n Those actions from our side
towards your company will have irreversible negative consequences for your business reputation.
\n\nYou don't care in any case, because you just don't want to pay? \n- We will make you business
stop forever by using all of our experience to make your partners, clients, employees and whoever
cooperates with your company change their minds by having no choice but to stay away from your
company. \nAs a result, in midterm you will have to close your business. \n\nSo lets get straight
to the point.\n\nWhat do we offer in exchange on your payment:\n- decryption and restoration of all
your systems and data within 24 hours with guarantee;\n- never inform anyone about the data breach
out from your company;\n- after data decryption and system restoration, we will delete all of your
data from our servers forever;\n- provide valuable advising on your company IT protection so no
one can hack you again.\n\nNow, in order to start negotiations, you need to do the following:\n-
install and run 'Tor Browser' from https://www.torproject.org/download/\n- use 'Tor Browser'
open <TA_URL_removed_by_analyst> \n- enter your ID or you will be banned and will never be able to
decrypt your files.\n\nThere will be live chat for your company after successful negotiations for
both sides. But there will be plenty of those bad cases of failed negotiations, so don't think about
how to avoid it.\nJust focus on negotiations, payment and describe to make all of your problems
solved by our specialists within 1 day after payment received: servers and data restored,
everything will work good as new.\n\n************************************************\n",
"note_short_text": "Your data is stolen and encrypted, see README_<extension_removed_by_analyst>.txt.", "settings":
{"local_disks"
Data Leak Site
The RansomHub ransom note contains a data leak site (DLS) that displayed the following page, self-identifying the group as RansomHub:
Figure 5. TOR DLS
Similarities with Other Ransomware
During our analysis, we observed some similarities between RansomHub, ALPHV/BlackCat, and Knight ransomware executables.
The following table highlights some of the similarities:
((uint16(0) == 0x5A4D) and (uint32(uint32(0x3C)) == 0x00004550)) and (9 of ($s*))
}
Recommended Mitigations
- Utilize an endpoint detection and response(EDR)solution withthe capability to halt detected processesand isolate systems on the network based on identified conditions.
- Block any known attacker C2sinthe firewall.
- Implement multi-factor authentication on RDP and VPN to restrict access to critical network resources.
- Eliminate unnecessary RDP ports exposed to the internet.
- Block a high number of SMB connection attempts from one system to othersinthe network over a short period of time.
- Perform periodic dark web monitoring to verify ifdata is available forsale on the black market.
- Perform penetration tests.
- Periodically patch systems and update tools.
- Monitor connections to the network from suspicious locations.
- Monitor downloads and uploads of files to file-sharing services outside standard work hours.
- Monitor file uploads from domain controllers to the internet.
- Monitor network scans from uncommon servers(e.g.,RDP server)
- Utilize an endpoint detection and response(EDR)solution withthe capability to halt detected processesand isolate systems on the network based on identified conditions.
- Block any known attacker C2sinthe firewall.
- Implement multi-factor authentication on RDP and VPN to restrict access to critical network resources.
- Eliminate unnecessary RDP ports exposed to the internet.
- Block a high number of SMB connection attempts from one system to othersinthe network over a short period of time.
- Perform periodic dark web monitoring to verify ifdata is available forsale on the black market.
- Perform penetration tests.
- Periodically patch systems and update tools.
- Monitor connections to the network from suspicious locations.
- Monitor downloads and uploads of files to file-sharing services outside standard work hours.
- Monitor file uploads from domain controllers to the internet.
- Monitor network scans from uncommon servers(e.g.,RDP server)
- Utilize an endpoint detection and response(EDR)solution withthe capability to halt detected processesand isolate systems on the network based on identified conditions.
- Block any known attacker C2sinthe firewall.
- Implement multi-factor authentication on RDP and VPN to restrict access to critical network resources.
- Eliminate unnecessary RDP ports exposed to the internet.
- Block a high number of SMB connection attempts from one system to othersinthe network over a short period of time.
- Perform periodic dark web monitoring to verify ifdata is available forsale on the black market.
- Perform penetration tests.
- Periodically patch systems and update tools.
- Monitor connections to the network from suspicious locations.
- Monitor downloads and uploads of files to file-sharing services outside standard work hours.
- Monitor file uploads from domain controllers to the internet.
- Monitor network scans from uncommon servers(e.g.,RDP server)
At Arete, we envision a world without cyber extortion, where people, businesses, and governments can thrive. We are taking all that we know from over 9,000 engagements to inform our solutions and strengthen powerful tools to better prevent, detect, and respond to the cyber extortion threats of tomorrow. Our elite team of experts provides unparalleled capabilities to address the entire cyber threat lifecycle, from incident response and restoration to advisory and managed security services. To learn more about our solutions, visit www.areteir.com.