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

Static analysis result for SHA-256 1cd5db9966a571ad…

MALICIOUS

Office (OLE) / .XLS

187.0 KB Created: 2020-06-22 16:20:38 Authoring application: Microsoft Excel
MD5: b6d41fd082a5b1061dd3da0b3be0b293 SHA-1: fd3b1128b07f49bcf0ca3df402dedf6dbffbb89c SHA-256: 1cd5db9966a571ad33eb30146039288c24cd13a94b47fd9813a98cf887023fa8
100 Risk Score

Malware Insights

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

The critical heuristic OLE_XLM_AUTOOPEN_DEFINEDNAME indicates the presence of an Excel 4.0 Auto_Open macro, which is designed to execute automatically when the workbook is opened. The SE_ENABLE_LURE heuristic and the document body text confirm that the sample attempts to trick the user into enabling editing, a common social engineering tactic to bypass macro security. The presence of an Auto_Open macro strongly suggests the intent is to download and execute a second-stage payload.

Heuristics 3

  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
adf670b2db277ab40d338f78d19b192cf334e26e9024f5f7da3bc780f2660bc3
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 124696 bytes