MalwareBazaar Database

You are currently viewing the MalwareBazaar entry for SHA256 31720bfa26640d3d2c7fe49b544596264d1886be023d62dcf0ffed3566c3ef81. 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


RemcosRAT


Vendor detections: 10


Maldoc score: 27


Intelligence 10 IOCs YARA 12 File information Comments
Download sample Add tag Delete this sample Report a False Positive

SHA256 hash: 31720bfa26640d3d2c7fe49b544596264d1886be023d62dcf0ffed3566c3ef81
SHA3-384 hash: 6dfa3ec3a96b8e4a72b50bb3f5785f87a80041d3b0af7f16679575beb9bcca351910e85f29c8da861f67ad61ef6404a5
SHA1 hash: 7df9542ca29c4e7a5d2386857f580d63e2e841b5
MD5 hash: e10c067bb6b61c4978eb54090c46bc67
humanhash: saturn-mississippi-vermont-burger
File name:INV_PR00102.xlsm
Download: download sample
Signature RemcosRAT
Create hunting rule
File size:16'937 bytes
First seen:2021-02-24 06:34:59 UTC
Last seen:Never
File type:Excel file xlsm
MIME type:application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
ssdeep 384:HnKkPZ2UlM9z6pRmyeYSpqC0smMS0uNsAbhmEac:qkR2xWpRjKqCqDtNsAbhmEH
TLSH E872C09E50E3A51DC766C9BF949A41FEEB8E00101BE7788D1941E62E72425CB860F4AA
Reporter abuse_ch
Tags:RAT RemcosRAT xlsm


Avatar
abuse_ch
Malspam distributing RemcosRAT:

HELO: mta.ham1001.secure.ne.jp
Sending IP: 150.60.232.66
From: Jennifer Longard <t.hawke@terrapex.com>
Reply-To: skydengroup@protonmail.com
Subject: Request for quotation
Attachment: INV_PR00102.xlsm

RemcosRAT C2:
skyden.awsmppl.com:44277

Office OLE Information

This malware samples appears to be an Office document. The following table provides more information about this document using oletools and oledump.

OLE id
Maldoc score: 27
OLE dump

MalwareBazaar was able to identify 14 sections in this file using oledump:

Section IDSection sizeSection name
A1569 bytesPROJECT
A2152 bytesPROJECTwm
A3991 bytesVBA/Sheet1
A43622 bytesVBA/ThisWorkbook
A53703 bytesVBA/_VBA_PROJECT
A61785 bytesVBA/__SRP_0
A7205 bytesVBA/__SRP_1
A8214 bytesVBA/__SRP_2
A9234 bytesVBA/__SRP_3
A10665 bytesVBA/dir
A111277 bytesVBA/dkihiwlkp
A122283 bytesVBA/dqeehzoww
A131580 bytesVBA/peoqadlzk
OLE vba

MalwareBazaar was able to extract and deobfuscate VBA script(s) the following information from OLE objects embedded in this file using olevba:

TypeKeywordDescription
AutoExecWorkbook_OpenRuns when the Excel Workbook is opened
Hex Stringdropped.ex64726f707065642e6578
Hex StringMSXML2.ServerXM4d53584d4c322e536572766572584d
Hex StringLHTTP.6.04c485454502e362e30
Hex StringUser55736572
Hex String-Agent2d4167656e74
Hex StringADODB.St41444f44422e5374
Hex Stringream7265616d
Hex StringWin32_ProcessS57696e33325f50726f6365737353
Hex Stringtartup746172747570
Hex StringWScr57536372
Hex Stringipt.Shell6970742e5368656c6c
SuspiciousEnvironMay read system environment variables
SuspiciousOpenMay open a file
SuspiciousWriteMay write to a file (if combined with Open)
SuspiciousSaveToFileMay create a text file
SuspiciousRunMay run an executable file or a system command
SuspiciousCreateMay execute file or a system command through WMI
SuspiciousShowWindowMay hide the application
SuspiciousCreateObjectMay create an OLE object
SuspiciousGetObjectMay get an OLE object with a running instance
SuspiciousChrMay attempt to obfuscate specific strings (use option --deobf to deobfuscate)
SuspiciousShellMay run an executable file or a system
SuspiciousWindowsMay enumerate application windows (if combined with Shell.Application object)
SuspiciousHex StringsHex-encoded strings were detected, may be used to obfuscate strings (option --decode to see all) 46e79

Intelligence

File Origin
# of uploads :
1
# of downloads :
89
Origin country :
n/a
Vendor Threat Intelligence
Malware family:
n/a
ID:
1
File name:
INV_PR00102.xlsm
Verdict:
Malicious activity
Analysis date:
2021-02-24 06:41:29 UTC
Tags:
macros macros-on-open rat remcos keylogger
Link:
https://app.any.run/tasks/6acd441e-e235-4b02-88aa-f94ffbd9cf87

Note:
ANY.RUN is an interactive sandbox that analyzes all user actions rather than an uploaded sample
Verdict:
Malicious
File type:
application/vnd.ms-excel.sheet.macroEnabled.12
Has a screenshot:
False
Contains macros:
True
Detection:
n/a
Link:
https://www.capesandbox.com/analysis/118804/
Detection(s):
Xls.Malware.Sload-7135989-0
Create hunting rule

TwinWave.EvilDoc.CROHeadGames.20200320.UNOFFICIAL
Create hunting rule

TwinWave.EvilDoc.CROKissFromARose.M2.20201210.UNOFFICIAL
Create hunting rule

TwinWave.EvilDoc.DOCXSTRGOOD.HTTPS
Create hunting rule

TwinWave.EvilDoc.DOCXRSTRGOOD.WIN32_PROCESS.200408.UNOFFICIAL
Create hunting rule

TwinWave.EvilDoc.DOCXRSTRGOOD.WINMGMTS
Create hunting rule

TwinWave.EvilDoc.DOCXRSTRGOOD.WIN32_PROCESS.200402.UNOFFICIAL
Create hunting rule

TwinWave.EvilDoc.GOVarVarJaneSays.20210125.UNOFFICIAL
Create hunting rule

Result
Verdict:
Malware
Maliciousness:

Behaviour
Creating a window
DNS request
Creating a file in the %temp% directory
Using the Windows Management Instrumentation requests
Creating a process with a hidden window
Creating a file
Creating a file in the %AppData% subdirectories
Connection attempt
Enabling autorun with the standard Software\Microsoft\Windows\CurrentVersion\Run registry branch
Unauthorized injection to a recently created process
Unauthorized injection to a recently created process by context flags manipulation
Setting a global event handler for the keyboard
Connection attempt to an infection source
Bypassing of proactive protection methods using Windows Management Instrumentation (WMI)
Sending a custom TCP request by exploiting the app vulnerability
Creating a process from a recently created file
Result
Verdict:
Malicious
File Type:
Excel File with Macro
Link:
https://app.docguard.net/31720bfa26640d3d2c7fe49b544596264d1886be023d62dcf0ffed3566c3ef81/results/dashboard
Result
Verdict:
MALICIOUS
Details
Macro with Startup Hook
Detected macro logic that will automatically execute on document open. Most malware contains some execution hook.
Macro Contains Suspicious String
Detected a macro with a suspicious string. Suspicious strings include privileged function calls, obfuscations, odd registry keys, etc...
InQuest Machine Learning
An InQuest machine-learning model classified this macro as potentially malicious.
Document With No Content
Document contains little or no semantic information.
Result
Threat name:
Remcos
Create hunting rule
Detection:
malicious
Classification:
troj.spyw.expl.evad
Score:
100 / 100
Link:
https://www.joesandbox.com/analysis/616497
Signature
C2 URLs / IPs found in malware configuration
Connects to a URL shortener service
Contains functionality to capture and log keystrokes
Contains functionality to inject code into remote processes
Contains functionality to register a low level keyboard hook
Contains functionality to steal Chrome passwords or cookies
Contains functionality to steal Firefox passwords or cookies
Creates processes via WMI
Delayed program exit found
Detected Remcos RAT
Detected unpacking (changes PE section rights)
Detected unpacking (overwrites its own PE header)
Document contains an embedded VBA macro which may execute processes
Document contains an embedded VBA macro with suspicious strings
Document contains an embedded VBA with functions possibly related to ADO stream file operations
Document contains an embedded VBA with functions possibly related to HTTP operations
Document contains an embedded VBA with hexadecimal encoded strings
Document exploit detected (creates forbidden files)
Document exploit detected (drops PE files)
Found malware configuration
Injects files into Windows application
Machine Learning detection for dropped file
Machine Learning detection for sample
Malicious sample detected (through community Yara rule)
Maps a DLL or memory area into another process
Multi AV Scanner detection for dropped file
Multi AV Scanner detection for submitted file
Office process drops PE file
Sigma detected: Remcos
Uses dynamic DNS services
Yara detected Remcos RAT
Behaviour
Behavior Graph:
Download SVG
behaviorgraph top1 dnsIp2 2 Behavior Graph ID: 357264 Sample: INV_PR00102.xlsm Startdate: 24/02/2021 Architecture: WINDOWS Score: 100 42 skyden.awsmppl.com 2->42 52 Found malware configuration 2->52 54 Malicious sample detected (through community Yara rule) 2->54 56 Multi AV Scanner detection for dropped file 2->56 58 16 other signatures 2->58 7 dropped.exe 1 21 2->7         started        11 notepad.exe 17 2->11         started        13 notepad.exe 17 2->13         started        15 EXCEL.EXE 16 9 2->15         started        signatures3 process4 dnsIp5 28 C:\Users\user\AppData\Roaming\...\notepad.exe, PE32 7->28 dropped 30 C:\Users\user\AppData\Local\...\System.dll, PE32 7->30 dropped 60 Multi AV Scanner detection for dropped file 7->60 62 Detected unpacking (changes PE section rights) 7->62 64 Detected unpacking (overwrites its own PE header) 7->64 78 4 other signatures 7->78 18 dropped.exe 2 3 7->18         started        32 C:\Users\user\AppData\Local\...\System.dll, PE32 11->32 dropped 66 Machine Learning detection for dropped file 11->66 68 Contains functionality to steal Chrome passwords or cookies 11->68 70 Contains functionality to capture and log keystrokes 11->70 22 notepad.exe 11->22         started        34 C:\Users\user\AppData\Local\Temp\7mf6.dll, PE32 13->34 dropped 36 C:\Users\user\AppData\Local\...\System.dll, PE32 13->36 dropped 72 Maps a DLL or memory area into another process 13->72 74 Injects files into Windows application 13->74 24 notepad.exe 13->24         started        48 cdn.discordapp.com 162.159.133.233, 443, 49166 CLOUDFLARENETUS United States 15->48 50 tinyurl.com 172.67.1.225, 443, 49165 CLOUDFLARENETUS United States 15->50 38 C:\Users\user\AppData\Local\...\dropped.exe, PE32 15->38 dropped 40 C:\Users\user\Desktop\~$INV_PR00102.xlsm, data 15->40 dropped 76 Document exploit detected (creates forbidden files) 15->76 file6 signatures7 process8 dnsIp9 44 skyden.awsmppl.com 45.153.203.165, 44277, 49167, 49168 NETLABFR Netherlands 18->44 46 skyden.duckdns.org 18->46 26 C:\Users\user\AppData\Roaming\...\logs.dat, ASCII 18->26 dropped file10
Detection:
n/a
Link:
https://mwdb.cert.pl/sample/31720bfa26640d3d2c7fe49b544596264d1886be023d62dcf0ffed3566c3ef81/
Threat name:
Script-Macro.Trojan.Valyria
Create hunting rule
Status:
Malicious
First seen:
2021-02-24 06:35:24 UTC
AV detection:
27 of 47 (57.45%)
Threat level:
  5/5
Detection(s):
Malicious file
Link:
https://check.spamhaus.org/check/?searchterm=gfzax6rgmqgt2ld74snvirmwezgrrbv6ai6wfxhq77wtkzwd56aq._file
Result
Malware family:
remcos
Create hunting rule
Score:
  10/10
Tags:
family:remcos macro persistence rat
Link:
https://tria.ge/reports/210224-8m42rsffla/
Behaviour
Checks processor information in registry
Enumerates system info in registry
Modifies Internet Explorer settings
Suspicious behavior: AddClipboardFormatListener
Suspicious behavior: EnumeratesProcesses
Suspicious behavior: MapViewOfSection
Suspicious use of FindShellTrayWindow
Suspicious use of SetWindowsHookEx
Suspicious use of WriteProcessMemory
NSIS installer
Office loads VBA resources, possible macro or embedded object present
Enumerates physical storage devices
Suspicious use of SetThreadContext
Adds Run key to start application
Loads dropped DLL
Executes dropped EXE
Remcos
Malware Config
C2 Extraction:
skyden.awsmppl.com:44277
skyden.duckdns.org:44277
Please note that we are no longer able to provide a coverage score for Virus Total.

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:ach_RemcosRAT
Create hunting rule
Author:abuse.ch
Rule name:Chrome_stealer_bin_mem
Create hunting rule
Author:James_inthe_box
Description:Chrome in files like avemaria
Rule name:Email_stealer_bin_mem
Create hunting rule
Author:James_inthe_box
Description:Email in files like avemaria
Rule name:INDICATOR_SUSPICIOUS_EXE_UACBypass_EventViewer
Create hunting rule
Author:ditekSHen
Description:detects Windows exceutables potentially bypassing UAC using eventvwr.exe
Rule name:IPPort_combo_mem
Create hunting rule
Author:James_inthe_box
Description:IP and port combo
Rule name:Keylog_bin_mem
Create hunting rule
Author:James_inthe_box
Description:Contains Keylog
Rule name:Parallax
Create hunting rule
Author:@bartblaze
Description:Identifies Parallax RAT.
Rule name:remcos_rat
Create hunting rule
Author:jeFF0Falltrades
Rule name:REMCOS_RAT_variants
Create hunting rule
Rule name:Select_from_enumeration
Create hunting rule
Author:James_inthe_box
Description:IP and port combo
Rule name:SharedStrings
Create hunting rule
Author:Katie Kleemola
Description:Internal names found in LURK0/CCTV0 samples
Rule name:UAC_bypass_bin_mem
Create hunting rule
Author:James_inthe_box
Description:UAC bypass in files like avemaria

File information

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

Malspam

RemcosRAT

Excel file xlsm 31720bfa26640d3d2c7fe49b544596264d1886be023d62dcf0ffed3566c3ef81

(this sample)

  
Delivery method
Distributed via e-mail attachment
Cape
Cape
https://www.capesandbox.com/analysis/118804/

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