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

Static analysis result for SHA-256 8d1fe6188829dd82…

MALICIOUS

Office (OLE) / .XLS

54.5 KB Created: 2020-10-28 08:15:02 Authoring application: Microsoft Excel
MD5: 292f50534fae7046270ff6e4b8cd52ef SHA-1: 2580cc325fac608e5bc90eb51763a1754ea3f762 SHA-256: 8d1fe6188829dd82b934bfb078993fe3c33b7fad2710e28f5c819261b6e9a152
180 Risk Score

Malware Insights

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

This Excel file contains Excel 4.0 (XLM) macros, specifically an Auto_Open macro, which is a known technique for executing malicious code. The heuristics indicate the presence of dangerous formula APIs and environment evasion, suggesting the macro is designed to run commands. While the specific commands are not fully extracted due to truncation, the presence of an Auto_Open macro strongly implies an intent to download and execute a secondary payload upon opening the file.

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.
  • XLM Auto_Open environment-evasion HALT gate high OLE_XLM_ENVIRONMENT_EVASION_HALT
    Excel 4.0 macro sheet auto-executes multiple GET.WORKSPACE / GET.WINDOW environment checks and halts execution when the host does not match the expected user environment. This is a common sandbox-evasion pattern in XLM malware and is stronger than a bare XLM macro-sheet indicator.
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
917a56b6f89880f491b5663e1e5a04f23891cc4a22a95e2fd43c077e5befa300		 xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 17251 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.