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

Static analysis result for SHA-256 071ca7e5a4e2146a…

MALICIOUS

Office (OLE) / .XLSX

150.5 KB Created: 2015-06-05 18:17:20 Authoring application: Microsoft Excel
MD5: 73e95f1b68d44e7a5eceae58f55c21ad SHA-1: b5aec6fd37019eec2142d1913d1f7d594e26f480 SHA-256: 071ca7e5a4e2146a96246e4bc5956096abd9910712db497ba52fe5679c4ed409
302 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

The sample contains a Workbook_Open VBA macro that utilizes CreateObject to execute a dropped payload. The macro attempts to reconstruct a command line from concatenated strings, which includes multiple URLs. These URLs are likely used to download and execute a second-stage payload, as indicated by the OLE_VBA_CELL_DROPPER_URL heuristic and the ClamAV detection name 'Doc.Downloader.EmotetExcel02226-9938630-0'. The reconstructed command line includes the string 'powershell -e <base64_encoded_payload>', suggesting the execution of a PowerShell payload.

Heuristics 8

  • URL reconstructed from VBA cell-staged base64 dropper (12 URLs) critical OLE_VBA_CELL_DROPPER_URL
    VBA reads worksheet cells, strips junk substrings via Replace(), and base64/UTF-16 decodes the result into a PowerShell EncodedCommand payload. The download URL is never contiguous in the file bytes; it was recovered by removing the macro's Replace() junk tokens from the cell strings and decoding the staged base64.
  • ClamAV: Doc.Downloader.EmotetExcel02226-9938630-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.EmotetExcel02226-9938630-0
  • Reference to Windows Script Host high SC_STR_WSCRIPT
    Reference to Windows Script Host
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject 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.
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code
  • 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://actividades.laforetlanguages.com/wp-admin/BlkdOKDXL/
    • http://sbcopylive.com.br/rjuz/w/
    • https://trasix.com/wp-admin/y5Aa1jt0Sp2Qk/
    • https://www.parkinsons.co.in/abc/Y6Y0fTbUEg6/
    • https://biz.merlin.ua/
    • http://bruckevn.site/3yztzzvh/nmY4wZfbYL/
    • https://pardiskood.com/wp-content/NR/
    • https://daujimaharajmandir.org/wp-includes/63De/
    • https://datasits.com/wp-includes/Zkj4QO/
    • https://anugerahmasinternasi
    • https://atmedic.cl/sistemas/3ZbsUAU/
    • https://anwaralbasateen.com/Fox-C404/mDHkfgebMRzmGKBy/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
006c4f4d54d1c9bb906763adb0bd849cdbbe9d88f3fa78ad2d18ef6987f96c37
vba-macro oletools.olevba.extract_macros (decoded VBA source) 8906 bytes