Malicious Office (OLE) / .XLS — malware analysis report

Static analysis result for SHA-256 b245d8399d4ffb77…

MALICIOUS

Office (OLE) / .XLS

367.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 00f93b62994d258d5fe5eb0753e472d2 SHA-1: 1fbc929b2e8c4cb2e579d4163c1ec6ed84223a9a SHA-256: b245d8399d4ffb777a42ff665991c69fb1b4260193c5ae7d91df831183442057
102 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File

The sample is an Excel 4.0 (XLM) macro-enabled spreadsheet. It contains an Auto_Open defined name, indicating that macros will execute automatically upon opening. The document body contains text that appears to be a lure to enable macros or editing. The extracted URLs are likely used to download a second-stage payload. The XLM macros themselves are truncated, but the presence of an Auto_Open entry and the embedded URLs strongly suggest a downloader or initial access pattern.

Heuristics 4

  • 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.
  • 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
  • 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://escolamundoazul.com.br/ntmQmwXnc6KC/ue.html In document text (OLE body)
    • https://laresumeservice.com/wp7rTKrY/ue.htmlIn document text (OLE body)

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
e0f9b32b2cf7d5bbad99732afb6eb8bf95619170305ebee6a87504bc690cca2a
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8209 bytes
Preview script
First 1,000 lines of the extracted script
' 0085     11 BOUNDSHEET : Sheet Information - worksheet or dialog sheet, visible - Doc1
' 0085     11 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible - Doc2
' 0085     11 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible - Doc3
' 0085     11 BOUNDSHEET : Sheet Information - Excel 4.0 macro sheet, visible - Doc4
' 0018     31 LABEL : Cell Value, String Constant - _xlfn.AGGREGATE hidden len=2 ptgErr  *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x1d'
' 0018     30 LABEL : Cell Value, String Constant - _xlfn.F.INV.RT hidden len=2 ptgErr  *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x1d'
' 0018     33 LABEL : Cell Value, String Constant - built-in-name 1 Auto_Open len=18 ptgRef3d 65535!A1 *UNKNOWN TOKEN* 0x0000 *INCOMPLETE FORMULA PARSING* Remaining, unparsed expression: b'\x00\x01\x00\x02\x00\x02\x00\x00\x00*'
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' 0204     21 LABEL : Cell Value, String Constant
' 0204     21 LABEL : Cell Value, String Constant
' 0204      9 LABEL : Cell Value, String Constant
' 0204     10 LABEL : Cell Value, String Constant
' 0204     11 LABEL : Cell Value, String Constant
' 0204      9 LABEL : Cell Value, String Constant
' 0204     10 LABEL : Cell Value, String Constant
' 0204     11 LABEL : Cell Value, String Constant
' 0204     11 LABEL : Cell Value, String Constant
' 0204     10 LABEL : Cell Value, String Constant
' 0204     12 LABEL : Cell Value, String Constant
' 0204     11 LABEL : Cell Value, String Constant
' 0204     11 LABEL : Cell Value, String Constant
' 0204     12 LABEL : Cell Value, String Constant
' 0204      9 LABEL : Cell Value, String Constant
' 0204     11 LABEL : Cell Value, String Constant
' 0204     10 LABEL : Cell Value, String Constant
' 0204     14 LABEL : Cell Value, String Constant
' 0204     33 LABEL : Cell Value, String Constant
' 0204     26 LABEL : Cell Value, String Constant
' 0204     10 LABEL : Cell Value, String Constant
' 0204     14 LABEL : Cell Value, String Constant
' 0204     26 LABEL : Cell Value, String Constant
' 0204     26 LABEL : Cell Value, String Constant
' 002a      2 PRINTHEADERS : Print Row/Column Labels
' Sheet,Reference,Formula,Value
' Doc2,BJ15,65534!A1,""
' Doc3,BQ6,"['*STACKERROR* not enough arguments for function: RAND=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)', '452354.00000000000000000000=SUMXMY2(45245)', '65534!A1']",""
' Doc3,BQ7,"['*STACKERROR* not enough arguments for function: RAND=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000000000000000000=SUMXMY2(45245))=FACT(59)=RAND(452354.00000
... (truncated)