MalwareBazaar Database

You are currently viewing the MalwareBazaar entry for SHA256 31caa6f66af8581cd7592d9b0e847127bfb2d28575b188ed178b36c3a7435693. 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


SilentBuilder


Vendor detections: 8


Maldoc score: 9


Intelligence 8 IOCs YARA 7 File information Comments
Download sample Add tag Delete this sample Report a False Positive

SHA256 hash: 31caa6f66af8581cd7592d9b0e847127bfb2d28575b188ed178b36c3a7435693
SHA3-384 hash: 0c33c4aa07da92d0f1d1d636573a2d1e9115a519944fd6327795ab4910a19164d8f154ffbc91ca57be847e604dafb282
SHA1 hash: d27cff39992cdbe0402fcfd80f5ad297cd95ec53
MD5 hash: cede243ccb2a1fb81284aa31eb65f126
humanhash: louisiana-two-xray-fix
File name:SecuriteInfo.com.Heur.7735.17404
Download: download sample
Signature SilentBuilder
Create hunting rule
File size:169'472 bytes
First seen:2021-02-18 20:16:54 UTC
Last seen:Never
File type:Excel file xlsx
MIME type:application/vnd.ms-excel
ssdeep 3072:XScKoSsxzNDZLDZjlbR868O8KlVH3jiKq7uDphYHceXVhca+fMHLtyeGxcl8OUMH:CcKoSsxzNDZLDZjlbR868O8KlVH3jiKS
TLSH F8F3CF5F7659CC52DA48033454E38BE26317FC9AABB387867A4CF6262FB06D04E1A507
Reporter SecuriteInfoCom
Tags:SilentBuilder

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: 9
Application name is Microsoft Excel
Office document is in OLE format
OLE dump

MalwareBazaar was able to identify 3 sections in this file using oledump:

Section IDSection sizeSection name
14096 bytesDocumentSummaryInformation
24096 bytesSummaryInformation
3158489 bytesWorkbook
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
AutoExecAuto_OpenRuns when the Excel Workbook is opened
Hex String54TT35345454
SuspiciousFORMULA.FILLMay modify Excel 4 Macro formulas at runtime
SuspiciousEXECMay run an executable file or a system
SuspiciousHex StringsHex-encoded strings were detected, may be used to obfuscate strings (option --decode to see all)
SuspiciousBase64 StringsBase64-encoded strings were detected, may be used to obfuscate strings (option --decode to see all)

Intelligence

File Origin
# of uploads :
1
# of downloads :
144
Origin country :
n/a
Vendor Threat Intelligence
Verdict:
Legit
File type:
application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
Has a screenshot:
False
Contains macros:
True
Detection:
n/a
Link:
https://www.capesandbox.com/analysis/117884/
Detection(s):
SecuriteInfo.com.Heur.7735.17404.UNOFFICIAL
Create hunting rule

TwinWave.EvilDoc.Excel4MagicPalmersArcade.20201207.UNOFFICIAL
Create hunting rule

TwinWave.EvilDoc.Excel4DragoTrainingMontage.20210204.UNOFFICIAL
Create hunting rule

Result
Verdict:
Malware
Maliciousness:

Behaviour
Creating a window
DNS request
Creating a process with a hidden window
Sending an HTTP GET request
Launching a process by exploiting the app vulnerability
Result
Verdict:
Malicious
File Type:
Legacy Office File
Link:
https://app.docguard.net/31caa6f66af8581cd7592d9b0e847127bfb2d28575b188ed178b36c3a7435693/results/dashboard
Payload URLs
URL
File name
http://www.iec.ch
WorkBook
Document image
Image:
Download PNG
Document image
Result
Verdict:
MALICIOUS
Details
Macro Execution Coercion
Detected a document that appears to social engineer the user into activating embedded logic.
Autostarting Excel Macro Sheet
Excel contains Macrosheet logic that will trigger automatically upon document open.
Result
Threat name:
Hidden Macro 4.0 TrickBot
Create hunting rule
Detection:
malicious
Classification:
troj.expl.evad
Score:
100 / 100
Link:
https://www.joesandbox.com/analysis/612063
Signature
Allocates memory in foreign processes
Delayed program exit found
Document exploit detected (drops PE files)
Document exploit detected (process start blacklist hit)
Document exploit detected (UrlDownloadToFile)
Drops PE files to the user root directory
Found evasive API chain (trying to detect sleep duration tampering with parallel thread)
Found Excel 4.0 Macro with suspicious formulas
Found malicious Excel 4.0 Macro
Office document tries to convince victim to disable security protection (e.g. to enable ActiveX or Macros)
Office process drops PE file
Sigma detected: Microsoft Office Product Spawning Windows Shell
Snort IDS alert for network traffic (e.g. based on Emerging Threat rules)
Tries to detect virtualization through RDTSC time measurements
Writes to foreign memory regions
Yara detected Trickbot
Behaviour
Behavior Graph:
Download SVG
behaviorgraph top1 signatures2 2 Behavior Graph ID: 355041 Sample: SecuriteInfo.com.Heur.7735.17404 Startdate: 18/02/2021 Architecture: WINDOWS Score: 100 36 Snort IDS alert for network traffic (e.g. based on Emerging Threat rules) 2->36 38 Found malicious Excel 4.0 Macro 2->38 40 Document exploit detected (drops PE files) 2->40 42 6 other signatures 2->42 8 EXCEL.EXE 84 41 2->8         started        process3 dnsIp4 34 artifkt.com 199.204.248.138, 49165, 80 AS17054US United States 8->34 24 C:\Users\user24Dks.freas, PE32 8->24 dropped 26 C:\Users\user\AppData\Local\...\8[1].fbr, PE32 8->26 dropped 48 Document exploit detected (process start blacklist hit) 8->48 50 Document exploit detected (UrlDownloadToFile) 8->50 13 rundll32.exe 8->13         started        file5 signatures6 process7 process8 15 rundll32.exe 25 13->15         started        signatures9 52 Writes to foreign memory regions 15->52 54 Allocates memory in foreign processes 15->54 56 Delayed program exit found 15->56 18 wermgr.exe 15->18         started        21 wermgr.exe 15->21         started        process10 dnsIp11 44 Tries to detect virtualization through RDTSC time measurements 18->44 46 Found evasive API chain (trying to detect sleep duration tampering with parallel thread) 18->46 28 108.170.20.75, 443 SSASN2US United States 21->28 30 94.140.114.136, 443 NANO-ASLV Latvia 21->30 32 194.5.249.156, 443 NXTHOST-64398NXTHOSTCOM-NXTSERVERSSRLRO Romania 21->32 signatures12
Detection:
n/a
Link:
https://mwdb.cert.pl/sample/31caa6f66af8581cd7592d9b0e847127bfb2d28575b188ed178b36c3a7435693/
Threat name:
Document-Word.Trojan.Heuristic
Create hunting rule
Status:
Malicious
First seen:
2021-02-18 20:17:11 UTC
AV detection:
5 of 47 (10.64%)
Threat level:
  2/5
Detection(s):
Suspicious file
Link:
https://check.spamhaus.org/check/?searchterm=ghfkn5tk7bmbzv2zfwnq5bdre673fuufowyyr3ixrm3mhj2dk2jq._file
Result
Malware family:
trickbot
Create hunting rule
Score:
  10/10
Tags:
family:trickbot botnet:rob59 banker macro trojan xlm
Link:
https://tria.ge/reports/210218-58lqj1qvq2/
Behaviour
Checks processor information in registry
Enumerates system info in registry
Modifies Internet Explorer settings
Suspicious behavior: AddClipboardFormatListener
Suspicious use of AdjustPrivilegeToken
Suspicious use of SetWindowsHookEx
Suspicious use of WriteProcessMemory
Loads dropped DLL
Templ.dll packer
Process spawned unexpected child process
Trickbot
Malware Config
C2 Extraction:
194.5.249.156:443
142.202.191.164:443
193.8.194.96:443
45.155.173.242:443
108.170.20.75:443
185.163.45.138:443
94.140.114.136:443
134.119.186.202:443
200.52.147.93:443
45.230.244.20:443
186.250.157.116:443
186.137.85.76:443
36.94.62.207:443
182.253.107.34:443
Dropper Extraction:
http://artifkt.com/okmobi/certificate.php
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:Email_stealer_bin_mem
Create hunting rule
Author:James_inthe_box
Description:Email in files like avemaria
Rule name:IPPort_combo_mem
Create hunting rule
Author:James_inthe_box
Description:IP and port combo
Rule name:multiple_concats_in_excel4_exec_enjoy_the_silence
Create hunting rule
Author:Will Metcalf
Description:Behold The Great And Powerful Match Iterator. Multiple Concats with register Function SILENT BUILDER EDITION
Reference:https://blog.reversinglabs.com/blog/excel-4.0-macros
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:SUSP_Excel4Macro_AutoOpen
Create hunting rule
Author:John Lambert @JohnLaTwC
Description:Detects Excel4 macro use with auto open / close
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.

Cape
Cape
https://www.capesandbox.com/analysis/117884/

Comments