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

Static analysis result for SHA-256 61c5ee9eb1b84008…

MALICIOUS

Office (OLE) / .XLS

525.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel First seen: 2021-05-29
MD5: 55a4b278af9871ddc12554e133df3d10 SHA-1: 481e1f221378a63890458ae3bc4a2c516b5b9490 SHA-256: 61c5ee9eb1b8400856e0846f59e481a5671dff56f0b884fc6586541187c44c19
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.005 Visual Basic T1203 Exploitation for Client Execution

The sample is an Excel 4.0 macro-enabled workbook that uses an 'enable content' lure to trick the user into running the macro. The macro uses the CALL and EXEC functions, indicating it attempts to execute external commands, likely to download and run a payload from one of the embedded URLs. The presence of these functions and the lure strongly suggests a malicious intent to compromise the user's system.

Heuristics 5

  • XLM Auto_Open workbook with payload URL or enable-content lure critical OLE_XLM_AUTOOPEN_PAYLOAD_LURE
    Workbook contains an Excel 4.0 macro sheet with Auto_Open / Auto_Close and also exposes a payload URL or enable-content lure in the OLE bytes. This combination is a high-confidence XLM downloader/social-engineering pattern even when formula recovery cannot decode the full macro chain.
  • Excel 4.0 (XLM) macro sheet uses dangerous capability functions high OLE_XLM_DANGEROUS_FN_STATIC
    Workbook contains an Excel 4.0 macro sheet whose formulas reference two or more dangerous capability functions (e.g. CALL into a Win32 API such as URLDownloadToFile, EXEC to launch a process, REGISTER an external DLL procedure, or FWRITE/FOPEN to drop a file) with an Auto_Open / Auto_Close auto-execution name. This is the canonical XLM downloader/dropper shape and is recovered directly from the BIFF records, so it fires even when the full macro chain cannot be deobfuscated.
  • 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 — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://aravindanavada.com/AHt5r3T0VSlq/solo.html In document text (OLE body)
    • https://mrcrgroup.com/sOyQynNJYBY/solo.htmlIn document text (OLE body)