Qbot — Office (OLE) / .XLS malware analysis

Static analysis result for SHA-256 f5fe36e39998e8f1…

MALICIOUS

Office (OLE) / .XLS

116.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: ddf4f1ca01b36bf2970d8ee732cb65a9 SHA-1: a35bfda5f4b2b28426900ef1df81d76c0279d949 SHA-256: f5fe36e39998e8f15809aed2c044437bb6fb58ca1bbd178644362a9aa5d32efb
262 Risk Score

Malware Insights

Qbot · confidence 95%

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

The sample is an Excel 4.0 macro-enabled spreadsheet that leverages the Auto_Open function to execute. The macro reconstructs and downloads payloads from three distinct URLs: "https://onlinegro.in/TsHT7OACCE2N/oi.html", "https://golba.com.br/MjFQ20bEM/oi.html", and "https://highsoftgroup.com/5Y0vwrgTcOB2/oi.html". ClamAV detection confirms this is a Qbot downloader.

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.
  • URL reconstructed from XLM cell array (3 URLs) critical OLE_XLM_CELL_ARRAY_URL
    Excel 4.0 macro sheet stages its payload URL across the BIFF8 Shared String Table (one quoted-char SST entry concatenated with & at runtime) or across individual numeric cells (one ASCII charcode per cell). The reconstructed URL is invisible to literal-bytes URL extraction because it is never contiguous in the workbook stream. URLs were recovered by walking the BIFF8 record stream and decoding SST entries plus LABELSST/RK/NUMBER cells.
  • ClamAV: Doc.Downloader.Qbot11202120-9906200-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Qbot11202120-9906200-0
  • 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.
  • 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://onlinegro.in/TsHT7OACCE2N/oi.html
    • https://golba.com.br/MjFQ20bEM/oi.html
    • https://highsoftgroup.com/5Y0vwrgTcOB2/oi.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
8b1b2317c70b581b924f86aea492873cbc610b9e51f97a7f89cf5cae96b94c55
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 11072 bytes