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

Static analysis result for SHA-256 1a5b07ad875ff013…

MALICIOUS

Office (OLE) / .XLS

280.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: 00b3e93aa50b54e4370685eac11359e0 SHA-1: 979caebf13a6a7bb3ce36ca4d63596bf98fe75d3 SHA-256: 1a5b07ad875ff013b0a98cab20382645f0465201b6b29a83b99b671a5240a40d
180 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.005 Visual Basic T1204 User Execution

The sample is an Excel 4.0 macro-enabled spreadsheet that impersonates a DocuSign signing request to trick the user into enabling macros. The presence of the Auto_Open macro and the reference to URLDownloadToFileA indicate that the macro is designed to download and execute a second-stage payload from one of the provided URLs. The macro execution is triggered automatically upon opening the document, as indicated by the Auto_Open defined name.

Heuristics 5

  • Reference to URLDownloadToFile API critical SC_STR_URLDOWNLOAD
    Reference to URLDownloadToFile API
  • 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
  • Document signing service impersonation lure medium SE_DOCUSIGN_LURE
    Document impersonates DocuSign, Adobe Sign, or a similar signing service in a signing-request context

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
c64ff06c8727bfaca53241723c990851e8edfec13b22dbdad50cbbd6ce2e9aed
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 3545 bytes