Office (OLE) / .XLS malware analysis — malicious · 644cf17e3f829680

MALICIOUS

Office (OLE) / .XLS

71.0 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel First seen: 2022-06-07

MD5: 911cbc803d3672c276d760c618651db6 SHA-1: db10182a1c00495217228d1d72051f5651338bcb SHA-256: 644cf17e3f829680979cf7e12c7d74c2731d836fb1880e7039b20320e67551ff

140 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1203 Exploitation for Client Execution

The critical heuristics indicate the presence of Excel 4.0 macros with an Auto_Open entry, which is a known technique for executing malicious code. The macros utilize dangerous formula APIs, including RUN, suggesting it attempts to download and execute a second-stage payload from the listed URLs. The presence of an Auto_Open function directly points to T1059.005 (Visual Basic) and T1203 (Exploitation for Client Execution).

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.
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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`xlm_macros.txt` `5111faade6798439ce43161a25c95a0c795073df8f05008e90c40cef2fd124d6`	xlm-macro	oletools.olevba.extract_all_macros (XLM macro listing)	7798 bytes

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