Office (OLE) / .XLSX malware analysis — malicious · 4f0f4780801b99f9

MALICIOUS

Office (OLE) / .XLSX

105.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel First seen: 2022-05-31

MD5: c3cb670f5a9d7cbfda34da5cad6a09d8 SHA-1: fbc7b779d409eef311bbb0ceb2e86a322ca093fb SHA-256: 4f0f4780801b99f92ae8c77ddf8937cab2c057d8a0c99fe49713a78c4306a52e

120 Risk Score

Malware Insights

MITRE ATT&CK

T1059.005 Visual Basic T1204.002 Malicious File

The presence of an Excel 4.0 Auto_Open macro sheet indicates that the document is designed to execute code upon opening. The document body and heuristics suggest a lure to impersonate DocuSign, prompting the user to enable macros. The extracted URLs are likely destinations for downloading a second-stage payload, and the 'rundll32 DllRegisterServer' command suggests a component registration or execution attempt.

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.
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
Document signing service impersonation lure medium SE_DOCUSIGN_LURE

Document impersonates DocuSign, Adobe Sign, or a similar signing service in a signing-request context

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`xlm_macros.txt` `1f3a9e9f425000bccc6ecbbba5371f1a3b0a17ea072b52992d451728caf3ab45`	xlm-macro	oletools.olevba.extract_all_macros (XLM macro listing)	3742 bytes

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