Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 1e2acdd9eb1b88fc…

MALICIOUS

Office (OLE)

319.5 KB Created: 2020-07-10 10:41:45 Authoring application: Microsoft Excel First seen: 2020-07-24
MD5: 6b75fc864cf99953ebd8e3ef0d0ddcdf SHA-1: 4b865bece4d2f786c7c4b758b9585f462eb760da SHA-256: 1e2acdd9eb1b88fcc4ca9effbc186dfdf551f7415c0a443a050cdd3a8f20a421
182 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic T1203 Exploitation for Client Execution

The sample is an Excel 4.0 macro-enabled document that uses an Auto_Open macro. The document body contains obfuscated text that appears to be an attempt to construct a URL. Heuristics indicate the presence of dangerous formula APIs and a lure to enable macros, common for malware delivery. The impersonation of a document signing service further supports a phishing or social engineering attack vector.

Heuristics 6

  • Excel 4.0 Auto_Open defined name critical OLE_XLM_AUTOOPEN_DEFINEDNAME
    oletools recovered an Auto_Open / Auto_Close entry from an Excel 4.0 macro sheet. The raw BIFF name can be tokenized or partially opaque to byte-string checks, but the recovered macro listing confirms the workbook has an XLM auto-execution entry.
  • XLM Auto_Open with dangerous formula APIs critical OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN
    Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings
  • Document signing service impersonation lure medium SE_DOCUSIGN_LURE
    Document impersonates DocuSign, Adobe Sign, or a similar signing service in a signing-request context
  • 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 http://www.w3.org/1999/02/22-rdf-syntax-ns# In document text (OLE body)
    • http://ns.adobe.com/xap/1.0/mm/In document text (OLE body)
    • http://ns.adobe.com/xap/1.0/sType/ResourceRef#In document text (OLE body)
    • http://ns.adobe.com/xap/1.0/In document text (OLE body)

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 73352 bytes
SHA-256: 4816f074acbc78439ec0879113c438dbdb4ae26aba507197504be5b2bb8f6383
Preview script
First 1,000 lines of the extracted script
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, very hidden -  Sheet
' 0085     10 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible -  C
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet
' 0085     26 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  bpzViVIjGEgOfRVvV
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet1
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet2
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet3
' 0085     15 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, hidden -  Sheet3
' 0085     14 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible -  Sheet
' 0018     19 LABEL : Cell Value, String Constant - aloE len=0 
' 0018     27 LABEL : Cell Value, String Constant - ardhHvsmFCZu len=0 
' 0018     23 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=7 ptgRef3d  Sheet!HO45181 
' 0018     25 LABEL : Cell Value, String Constant - BdLcOSrSdX len=0 
' 0018     61 LABEL : Cell Value, String Constant - BEvUxcaIwRIxMWFFrsTcoRkPnGSGDwPMjTdjfrIJegpNuY len=0 
' 0018     61 LABEL : Cell Value, String Constant - bpziiVVwFStNsRiuigaspMvHNJUlmIJTqXBQwEWeUzuvty len=0 
' 0018     39 LABEL : Cell Value, String Constant - BrGQyylYyViwevhlLzwqJGcy len=0 
' 0018     27 LABEL : Cell Value, String Constant - BsdLNhKPcZIV len=0 
' 0018     47 LABEL : Cell Value, String Constant - buDrXTTSXIBImNyPSVNlPtdZOiYPdnWW len=0 
' 0018     57 LABEL : Cell Value, String Constant - CDMkRuKqwQYOtopnsdWeIjUkoqiIkPzvjFulzKssfS len=0 
' 0018     48 LABEL : Cell Value, String Constant - CfhOhnvkQZaYdBHPsGFVZbTsIzkSUpRWk len=0 
' 0018     37 LABEL : Cell Value, String Constant - cMuwRtyMWrFseGcbDkCnrS len=0 
' 0018     23 LABEL : Cell Value, String Constant - crYexGvb len=0 
' 0018     26 LABEL : Cell Value, String Constant - CSVYQoSwgcR
... (truncated)