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

Static analysis result for SHA-256 24ef37668e399c4f…

MALICIOUS

Office (OLE) / .XLS

65.6 KB Created: 2022-01-17 17:40:35 Authoring application: Microsoft Excel
MD5: 0864446ff270ebca8e1ff17960534d6f SHA-1: 466a54d1db60ed0adae1fe3a45c4acf338f9cb51 SHA-256: 24ef37668e399c4f9a1a0d5f389bea539d0092fe2688f266ce9e35e2a0af7d95
100 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 User Execution: Malicious File T1059.005 Command and Scripting Interpreter: Visual Basic for Applications T1105 Ingress Tool Transfer T1027 Obfuscation

The sample uses a 'protected' document lure to trick the user into enabling macros. The embedded Excel 4.0 (XLM) macros execute a shell command to download a payload from 'http://0xc12a24f5/c.html' and 'http://0xc12a24f5/cc.html' via the 'cmd /c m^sh^t^a' (mshta) gesture. The use of caret symbols for obfuscation in the command line is a typical dropper behavior.

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
0807f652a36752efcd354ce3c536f2fe7ed4cd53a3ff1787c33acb378dda90a0
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 1073 bytes