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

Static analysis result for SHA-256 35974fd45d14bf0d…

MALICIOUS

Office (OLE) / .XLSX

699.0 KB Created: 2020-06-22 10:41:03 Authoring application: Microsoft Excel
MD5: 80c6c805b27951070e576c80b4e35fd5 SHA-1: 1146b6a948611f41cddcc5d4a361b8b4516d1f88 SHA-256: 35974fd45d14bf0d37a311b0a531655b769c9be30ac76e21d70ffbd9d023e9e5
340 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1059.003 Windows Command Shell T1204.002 Malicious File

The sample is an Excel file containing a Workbook_Open macro that utilizes the Shell() function. This macro is designed to execute a command, likely to download and run a second-stage payload. The ClamAV detection of 'Xls.Packed.Logan-9738662-0' further confirms its malicious nature. The document body contains what appears to be a filename and a Base64 encoded string, which may be related to the payload.

Heuristics 8

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • ClamAV: Xls.Packed.Logan-9738662-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Packed.Logan-9738662-0
  • Reference to Windows Script Host high SC_STR_WSCRIPT
    Reference to Windows Script Host
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
c002a21b25eb16c7cf03a813431739fc85b8749f5f8d813ff87921f514f0b8e4
vba-macro oletools.olevba.extract_macros (decoded VBA source) 22654 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved macro source contains an auto-exec entry point and execution/download terms.
ole10native_00.bin
50bbdd9fbbbbfb058d8ce90c36c6dd737df05c51155ec25e62815722e58296e1
ole-package OLE Ole10Native stream: MBD00356439/Ole10Native 439791 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.98, consistent with packed or encrypted content.