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

Static analysis result for SHA-256 4f7f07dc1bdc7ffc…

MALICIOUS

Office (OLE) / .XLS

380.5 KB Created: 2015-06-05 18:19:34 Authoring application: Microsoft Excel
MD5: c5869eae49189b424c4210b72a1e2803 SHA-1: 4e037a5b03f5d2a969dd53fc816c77d9b85ce8bb SHA-256: 4f7f07dc1bdc7ffc49a38e58d54209c24076122519a3c02080c4ee838c6ebde7
102 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File

The critical heuristic OLE_XLM_AUTOOPEN_DEFINEDNAME indicates the presence of an Excel 4.0 macro sheet with an Auto_Open entry, which is designed to execute automatically when the workbook is opened. The SE_ENABLE_LURE heuristic suggests the document prompts the user to enable macros, a common social engineering tactic. The embedded URLs are likely used to download a second-stage payload. The XLM macros themselves were too large to fully analyze but are confirmed to exist.

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
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — context-specific rules above attribute URLs they actually evaluated; this rule lists URLs that were present in the bytes but were not otherwise tied to a specific finding.
    URL https://caiogabriel.com.br/tOKLlSLW/lena.html
    • https://bwctradex.com/BcotoLXTr1y/lena.html

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
d46ad6b52df62d280ddc3eb28f4fdfc78bc84dc99077b9aa50809affc4be6057
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 8812 bytes