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

Static analysis result for SHA-256 c1d8476db257bb66…

MALICIOUS

Office (OLE) / .XLS

180.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 0902144f29c40ef477b961e107ab0ff3 SHA-1: b3245eabe323cfddc6825bf740733f7a09a63f7a SHA-256: c1d8476db257bb666c05ffb80e4e2aab3e04b4af8ef18365f2558e5bbe9f1884
160 Risk Score

Malware Insights

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

The sample contains Excel 4.0 macros, specifically an Auto_Open function, which is a critical finding. This function is designed to execute automatically when the document is opened, and it utilizes dangerous formula APIs. The document body lists several URLs, indicating the macro's intent is to download and execute a second-stage payload from one of these locations. The presence of the 'SE_ENABLE_LURE' heuristic further suggests the document attempts to trick the user into enabling macros.

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.
  • 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.
  • 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
917baaae0e48794e5eb73ae3d5cf93c43110b97da5df3e45bc2f236b5551c875
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 27158 bytes