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

Static analysis result for SHA-256 a4c1c04d6bf94a01…

MALICIOUS

Office (OLE) / .XLS

1.66 MB Created: 2016-04-08 13:33:00 Authoring application: Microsoft Excel First seen: 2023-10-18
MD5: 3e6ed773fcd2cc9618c8220d150a3b68 SHA-1: 4917ef95c2b2f1c0ad0a18700a60c5dc16ea4cb8 SHA-256: a4c1c04d6bf94a012f4abf50aac9b0253f0b72d18bbb5e832b2caa1e12d9be89
482 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1059.001 PowerShell T1204.002 Malicious File T1566.001 Spearphishing Attachment T1071.001 Web Protocols

The sample is an Excel spreadsheet containing obfuscated VBA macros, including a Workbook_Open event that attempts to execute code via WScript.Shell. This indicates a downloader or droppper functionality designed to run a second-stage payload. The presence of a password protection lure suggests an attempt to bypass gateway scanning.

Heuristics 12

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • WScript.Shell usage critical OLE_VBA_WSCRIPT
    WScript.Shell usage
  • Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER
    Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
  • 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
  • GetObject call high OLE_VBA_GETOBJ
    GetObject 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.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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
  • 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 http://www.frez.co.uk

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
16b1e137f4a105c7a1730eef9dbda51c43de37ce03813fc7c4aceba03120f72a
vba-macro oletools.olevba.extract_macros (decoded VBA source) 1444515 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).