MalwareBazaar Database

You are currently viewing the MalwareBazaar entry for SHA256 4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9. While MalwareBazaar tries to identify whether the sample provided is malicious or not, there is no guarantee that a sample in MalwareBazaar is malicious.

Database Entry


QuasarRAT


Vendor detections: 16


Intelligence 16 IOCs YARA 6 File information Comments
Download sample Add tag Delete this sample Report a False Positive

SHA256 hash: 4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9
SHA3-384 hash: 384f1119dceaf24b69743dd9333516f47a9c28e0fecd81acd9da734d8cda5beae430402860ef4990becd3aef267dcd10
SHA1 hash: acb20c0c56da6085bc9508bd9fa6ee25d6ef92df
MD5 hash: 4ae7fa0777d1d79d3ecb39c3b709189d
humanhash: neptune-iowa-illinois-salami
File name:built_crypted.exe
Download: download sample
Signature QuasarRAT
Create hunting rule
File size:5'348'352 bytes
First seen:2025-09-08 11:37:55 UTC
Last seen:Never
File type:Executable exe
MIME type:application/x-dosexec
imphash f34d5f2d4577ed6d9ceec516c1f5a744 (48'652 x AgentTesla, 19'463 x Formbook, 12'204 x SnakeKeylogger)
ssdeep 49152:uQHlEQpMxabpmQb6FEPcSUu0Juw5y5SfRfPfoTov7SjZszqg/3wwsIRF16Z0O:
Threatray 108 similar samples on MalwareBazaar
TLSH T14F36DC383BEAD0197273EE564AD474A7A95FB7B37B03944E206103464633941EEE2D3E
TrID 71.1% (.EXE) Generic CIL Executable (.NET, Mono, etc.) (73123/4/13)
10.2% (.EXE) Win64 Executable (generic) (10522/11/4)
6.3% (.DLL) Win32 Dynamic Link Library (generic) (6578/25/2)
4.3% (.EXE) Win32 Executable (generic) (4504/4/1)
2.0% (.ICL) Windows Icons Library (generic) (2059/9)
Magika pebin
Reporter abuse_ch
Tags:exe QuasarRAT

Intelligence

File Origin
# of uploads :
1
# of downloads :
77
Origin country :
SE SE
Vendor Threat Intelligence
Malware family:
n/a
ID:
1
File name:
built_crypted.exe
Verdict:
Malicious activity
Analysis date:
2025-09-07 23:13:47 UTC
Tags:
auto-reg api-base64 xor-url generic crypto-regex
Link:
https://app.any.run/tasks/d78a91ad-9b79-41eb-a546-8bd9a7ca6e7a

Note:
ANY.RUN is an interactive sandbox that analyzes all user actions rather than an uploaded sample
Detection:
n/a
Link:
https://www.capesandbox.com/analysis/26247/
Verdict:
Malicious
Score:
99.9%
Link:
https://cyber-fortress.com/docs/result/index.php?id=68be11adb20052598878d430
Tags:
autorun micro spawn sage
Result
Verdict:
Malware
Maliciousness:

Behaviour
Creating a window
Сreating synchronization primitives
Creating a file in the %AppData% subdirectories
Launching a process
Enabling the 'hidden' option for recently created files
Creating a process from a recently created file
Creating a file
DNS request
Connection attempt
Setting a keyboard event handler
Sending a custom TCP request
Unauthorized injection to a recently created process
Enabling autorun by creating a file
Verdict:
Likely Malicious
Threat level:
  7.5/10
Confidence:
100%
Tags:
anti-vm cryptor_detected obfuscated obfuscated packed
Link:
https://www.filescan.io/uploads/68bec047532ebbcda8d17dc3/reports/f46b0654-2538-45ea-8d84-c5478273467c/overview
Verdict:
Malicious
Labled as:
MSILKrypt.Generic
Link:
https://www.hybrid-analysis.com/sample/4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9
Verdict:
Malicious
File Type:
exe x32
First seen:
2025-09-07T20:16:00Z UTC
Last seen:
2025-09-07T20:16:00Z UTC
Hits:
~10
Detections:
HEUR:Trojan.Win32.Generic HEUR:Trojan.MSIL.Quasar.gen PDM:Trojan.Win32.Tasker.cust PDM:Trojan.Win32.Generic Trojan-PSW.MSIL.Agent.sb Trojan.MSIL.Quasar.a Trojan.MSIL.Crypt.sb
Link:
https://opentip.kaspersky.com/4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9/results?tab=lookup
Verdict:
Malicious
Link:
https://analyze.intezer.com/analyses/c5b91bc5-5ebd-40ba-8bdf-c2d90b04f8e1
Result
Threat name:
Quasar
Create hunting rule
Detection:
malicious
Classification:
troj.spyw.evad
Score:
100 / 100
Link:
https://www.joesandbox.com/analysis/1773065
Signature
.NET source code contains potential unpacker
.NET source code contains very large strings
Antivirus / Scanner detection for submitted sample
Antivirus detection for dropped file
Connects to many ports of the same IP (likely port scanning)
Found malware configuration
Hides that the sample has been downloaded from the Internet (zone.identifier)
Installs a global keyboard hook
Multi AV Scanner detection for dropped file
Multi AV Scanner detection for submitted file
Sample uses string decryption to hide its real strings
Uses schtasks.exe or at.exe to add and modify task schedules
Yara detected Quasar RAT
Behaviour
Behavior Graph:
Download SVG
behaviorgraph top1 dnsIp2 2 Behavior Graph ID: 1773065 Sample: built_crypted.exe Startdate: 08/09/2025 Architecture: WINDOWS Score: 100 31 PulsarKDOT-54096.portmap.host 2->31 43 Found malware configuration 2->43 45 Antivirus / Scanner detection for submitted sample 2->45 47 Multi AV Scanner detection for submitted file 2->47 49 5 other signatures 2->49 9 built_crypted.exe 5 2->9         started        13 RealtekAudioDriverUpdater.exe 3 2->13         started        signatures3 process4 file5 27 C:\Users\...\RealtekAudioDriverUpdater.exe, PE32 9->27 dropped 29 C:\Users\user\...\built_crypted.exe.log, CSV 9->29 dropped 51 Uses schtasks.exe or at.exe to add and modify task schedules 9->51 53 Hides that the sample has been downloaded from the Internet (zone.identifier) 9->53 15 RealtekAudioDriverUpdater.exe 2 9->15         started        19 schtasks.exe 1 9->19         started        signatures6 process7 dnsIp8 33 PulsarKDOT-54096.portmap.host 193.161.193.99, 49691, 49693, 49695 BITREE-ASRU Russian Federation 15->33 35 Antivirus detection for dropped file 15->35 37 Multi AV Scanner detection for dropped file 15->37 39 Hides that the sample has been downloaded from the Internet (zone.identifier) 15->39 41 Installs a global keyboard hook 15->41 21 schtasks.exe 1 15->21         started        23 conhost.exe 19->23         started        signatures9 process10 process11 25 conhost.exe 21->25         started       
Score:
100%
Verdict:
Malware
File Type:
PE
Link:
https://malprob.io/report/4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9
Verdict:
inconclusive
YARA:
10 match(es)
Tags:
.Net Executable Managed .NET PE (Portable Executable) PE File Layout SOS: 0.03 Win 32 Exe x86
Link:
https://app.malva.re/file/4ae7fa0777d1d79d3ecb39c3b709189d
Detection:
n/a
Link:
https://mwdb.cert.pl/sample/4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9/
Verdict:
Malicious
Threat:
Trojan.MSIL.Quasar
Link:
https://tip.neiki.dev/file/4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9
Threat name:
ByteCode-MSIL.Trojan.Nekark
Create hunting rule
Status:
Malicious
First seen:
2025-09-07 23:13:48 UTC
File Type:
PE (.Net Exe)
Extracted files:
1
AV detection:
25 of 38 (65.79%)
Threat level:
  5/5
Detection(s):
Suspicious file
Link:
https://check.spamhaus.org/check/?searchterm=j6brx7ovwovx6qmuw36tshfmog3qxj6o2nej5mv566axb2ysctuq._file
Verdict:
malicious
Label(s):
quasarrat
Create hunting rule
Similar samples:
4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9
QuasarRAT
62e2c7d860a0e3e0975c5b9da5193f9ab3ca6c56ef4eea46d17cc87ac4598b90
QuasarRAT
9f8b05f57597f6a61089e954ea1c2dfa24f1a4a72c5a2ff883a9fabb1203f658
QuasarRAT
e553c34b8aabb6ad42dfdb8a77759b32c6c035f2fc82618eefa2261c71dee761
QuasarRAT
eb72d6dd2158ce9ad453f8ecfd5d6900cce588c196ae5806268cbaf3475848da
QuasarRAT
error
QuasarRAT
f66a4ee15f672bbf9259027eb286f369bfa81a3aa979f547415b831d22d031b5
QuasarRAT
f879f50e21830b34b77fd94a33b6c395b9837bb701a7f5e4dad2e9d287af9e72
QuasarRAT
+ 98 additional samples on MalwareBazaar
Result
Malware family:
n/a
Score:
  7/10
Tags:
execution persistence
Link:
https://tria.ge/reports/250908-nr4r4sbl91/
Behaviour
Scheduled Task/Job: Scheduled Task
Suspicious behavior: AddClipboardFormatListener
Suspicious use of AdjustPrivilegeToken
Suspicious use of SetWindowsHookEx
Suspicious use of WriteProcessMemory
Uses Task Scheduler COM API
Executes dropped EXE
Verdict:
Malicious
Tags:
n/a
YARA:
n/a
Link:
https://app.threat.zone/submission/b7516144-c802-46ed-a391-d8ad4fe3bfa2
Unpacked files
SH256 hash:
4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9
MD5 hash:
4ae7fa0777d1d79d3ecb39c3b709189d
SHA1 hash:
acb20c0c56da6085bc9508bd9fa6ee25d6ef92df
Link:
https://www.unpac.me/results/f6d50189-4f3b-4c7f-9e2a-be51dcc7bf88/
SH256 hash:
085f01b69726bf4a6b116a8816c85d49ebb747b764e43d6830a01c7d54587da7
MD5 hash:
f49357c6ef061663c292663537ab04fc
SHA1 hash:
58c3c22580d43728ad19f92b4c55e7ede6c145bf
Detections:
INDICATOR_EXE_Packed_Fody
Create hunting rule
Link:
https://www.unpac.me/results/f6d50189-4f3b-4c7f-9e2a-be51dcc7bf88/
SH256 hash:
52baff5ea0f63cf37ae0cc5a77504ee22491cefb4e61a51c1b4d157511916c35
MD5 hash:
839dd924eb6e9e5672d79241c8ae292d
SHA1 hash:
c191c6ee754956190667ad971f8abfaed8eacc92
Detections:
SUSP_NET_Large_Static_Array_In_Small_File_Jan24
Create hunting rule
HKTL_NET_GUID_Quasar
Create hunting rule
Link:
https://www.unpac.me/results/f6d50189-4f3b-4c7f-9e2a-be51dcc7bf88/
Parent samples :
e553c34b8aabb6ad42dfdb8a77759b32c6c035f2fc82618eefa2261c71dee761
62e2c7d860a0e3e0975c5b9da5193f9ab3ca6c56ef4eea46d17cc87ac4598b90
eb72d6dd2158ce9ad453f8ecfd5d6900cce588c196ae5806268cbaf3475848da
6e6e691a7f98fc4086f2bec28b34b2474ab783e9408c611e789a00107a24c227
7e4fe2503e3dd2028c230f5e0413423f1dbbcbda01a252d22c8ece243979e927
4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9
b6d7379d42b82f6e3943837a34a74936f230cdfbb3ff2d19f1517466492af7c2
Please note that we are no longer able to provide a coverage score for Virus Total.
Threat name:
iSpy Keylogger
Score:
1.00
Link:
https://yomi.yoroi.company/submissions/4f831bfdd5b3ab7f4194b6fd391cac71b70ba7ced3489eb2bdf78170eb1214e9

YARA Signatures

MalwareBazaar uses YARA rules from several public and non-public repositories, such as YARAhub and Malpedia. Those are being matched against malware samples uploaded to MalwareBazaar as well as against any suspicious process dumps they may create. Please note that only results from TLP:CLEAR rules are being displayed.

Rule name:CP_AllMal_Detector
Create hunting rule
Author:DiegoAnalytics
Description:CrossPlatform All Malwares Detector: Detect PE, ELF, Mach-O, scripts, archives; overlay, obfuscation, encryption, spoofing, hiding, high entropy, network communication
Rule name:DebuggerCheck__PEB
Create hunting rule
Reference:https://github.com/naxonez/yaraRules/blob/master/AntiDebugging.yara
Rule name:NETexecutableMicrosoft
Create hunting rule
Author:malware-lu
Rule name:pe_imphash
Create hunting rule
Rule name:Skystars_Malware_Imphash
Create hunting rule
Author:Skystars LightDefender
Description:imphash
Rule name:Sus_CMD_Powershell_Usage
Create hunting rule
Author:XiAnzheng
Description:May Contain(Obfuscated or no) Powershell or CMD Command that can be abused by threat actor(can create FP)

File information

The table below shows additional information about this malware sample such as delivery method and external references.

Cape
Cape
https://www.capesandbox.com/analysis/26247/

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