Office (OLE) / .XLS malware analysis — malicious · 91ff74a56295a59c

MALICIOUS

Office (OLE) / .XLS

164.0 KB Created: 2020-03-23 21:31:38 Authoring application: Microsoft Excel

MD5: 5718982971b529c7a954f087385c2f52 SHA-1: be758ffc0e606ac4d7abdf4427e7f49fe5c20835 SHA-256: 91ff74a56295a59c831684759bca334e72e3aa596fffb47eabe43e8c657f7fa8

320 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1059.001 PowerShell T1204.002 Malicious File

The file is an Excel spreadsheet containing VBA macros. A critical heuristic firing indicates the presence of a Workbook_Open macro that uses a character-shift decoder to execute a shell command. This suggests the macro is designed to download and execute a second-stage payload. ClamAV detection as 'Xls.Dropper.Agent-7640839-0' further supports its malicious nature as a dropper.

Heuristics 7

Shell() call in VBA critical OLE_VBA_SHELL

Shell() call in VBA
VBA character-shift decoded Shell command critical OLE_VBA_ASC_CHR_SHIFT_SHELL

VBA auto-exec macro stores an encoded command string, decodes it with a Mid/Asc/Chr character-shift loop, and passes the recovered text to Shell. This is a high-confidence command stager.
ClamAV: Xls.Dropper.Agent-7640839-0 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Xls.Dropper.Agent-7640839-0
Workbook_Open macro high OLE_VBA_WBOPEN

Workbook_Open macro
VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC

Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
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.
VBA macros detected medium OLE_VBA_MACROS

Document contains VBA macro code

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`macros.bas` `bad3faf83aaa5b74afe19adfafed48a77af972d94f8c00651ddb433e9c18bad5`	vba-macro	oletools.olevba.extract_macros (decoded VBA source)	2719 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.