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

Static analysis result for SHA-256 0b9ff3504c3ab7ff…

MALICIOUS

Office (OLE) / .XLS

380.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: 0a7252d070e453ebd83515ea8278fecc SHA-1: d0738dace2fb6ec94545c212d4bc5bb54fb182bb SHA-256: 0b9ff3504c3ab7ff9fb7b2b9530f5cb412a315c7dc750364ddfae010ee565409
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic T1204.002 Malicious File

The sample is an Excel file containing Excel 4.0 macros, specifically an Auto_Open macro designed to execute automatically. The macros are obfuscated but appear to construct URLs and execute a file using 'rundll32.exe'. The document also contains a lure to enable macros, indicating a malicious intent to bypass security measures. The extracted URLs are likely used to download and execute a second-stage payload.

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://hermescomm.net/x9NvrhL0/lena.html
    • https://asistenciajuridicaintegral.com/6YiCkNix5/lena.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
be629cb484f8d82e38c4234ddbad4f1755e762b9c1c8359642d99f8c77e6e858
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8812 bytes