Xls.Dropper.Agent-7079703-0 — Office (OLE) malware analysis

Static analysis result for SHA-256 aaa1054a21e31bc8…

MALICIOUS

Office (OLE)

633.4 KB Created: 2003-07-13 10:04:24 Authoring application: Microsoft Excel First seen: 2019-04-18
MD5: 05ab6e2947a32d84b88b8f335b3aa190 SHA-1: 64764e2dbbc0bd38881e013b418029d294638cd1 SHA-256: aaa1054a21e31bc80fafee4161b6fa80f88df2f9a9fe9db6fb1a3a0768429748
602 Risk Score

Malware Insights

Xls.Dropper.Agent-7079703-0 · confidence 95%

MITRE ATT&CK
T1204.002 Malicious File T1105 Ingress Tool Transfer

The sample is an Excel document identified by ClamAV as 'Xls.Dropper.Agent-7079703-0'. It contains multiple embedded PE executables and OLE objects, indicating a dropper functionality. Heuristics for CreateProcess, ShellExecute, and URLDownloadToFile suggest the file's intent is to download and execute additional malicious content. The presence of embedded executables strongly supports this dropper behavior.

Heuristics 14

  • ClamAV: Win.Trojan.Agent-6943819-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Trojan.Agent-6943819-1
  • Reference to URLDownloadToFile API critical SC_STR_URLDOWNLOAD
    Reference to URLDownloadToFile API
  • Embedded PE executable critical OLE_EMBEDDED_EXE
    MZ/PE header found inside document — possible embedded executable
  • Embedded Office document has suspicious static findings critical EMBEDDED_OFFICE_CHILD_STATIC_TRIAGE
    A CFB/OLE Office document was found inside another file type and its carved contents matched Office exploit or payload heuristics. This catches wrapped exploit documents where the top-level file routes to a PE, archive, or generic scanner instead of Office.
  • Reference to CreateProcess API high SC_STR_CREATEPROCESS
    Reference to CreateProcess API
  • Reference to ShellExecute API high SC_STR_SHELLEXEC
    Reference to ShellExecute API
  • Reference to LoadLibrary API high SC_STR_LOADLIBRARY
    Reference to LoadLibrary API
  • Reference to GetProcAddress API high SC_STR_GETPROCADDRESS
    Reference to GetProcAddress API
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 648,591 bytes but its declared streams total only 12,288 bytes — 636,303 bytes (98%) live in unallocated sector slack. This is the canonical hiding place for pre-macro-era Office exploit payloads (XOR-encoded shellcode reached via a parser pointer-corruption bug in the document structure).
  • 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.
  • Reference to VirtualAlloc API medium SC_STR_VIRTUALALLOC
    Reference to VirtualAlloc API
  • Reference to VirtualProtect API medium SC_STR_VIRTUALPROTECT
    Reference to VirtualProtect API
  • CFB header with no readable streams medium OLE_PARSE_EMPTY_STREAMS
    The file begins with a valid OLE2/CFB header but exposes no directory streams. A non-empty compound document with an unreadable directory is anomalous — it is seen with truncated/corrupt files and, more importantly, with content deliberately shifted off byte boundaries to defeat parsers while the host application still recovers the object.
  • 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://ocsp.verisign.com0 In document text (OLE body)
    • http://crl.verisign.com/ThawteTimestampingCA.crl0In document text (OLE body)
    • http://crl.verisign.com/tss-ca.crl0In document text (OLE body)
    • http://crl.microsoft.com/pki/crl/products/CodeSignPCA2.crl0OIn document text (OLE body)
    • http://www.microsoft.com/pki/certs/CodeSignPCA2.crt0In document text (OLE body)
    • http://office.microsoft.comIn document text (OLE body)

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_office_0000660a.exe embedded-pe Office MZ+PE at offset 0x660A 622469 bytes
SHA-256: 487ff8699383e74a2c437f47980b787fffb5d25b0626c436935b0fa8fe332dfc
Detection
ClamAV: Win.Trojan.Agent-6943819-1
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln
embedded_office_off00003605.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x3605 634762 bytes
SHA-256: 5c7e968bfcea58a98bc6ea06e7902f91645e619103b6232e405bfc29bd605cb1
Detection
ClamAV: Win.Trojan.Agent-6943819-1
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln
embedded_office_off00006480.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x6480 622863 bytes
SHA-256: 47de3ff7057e9598f819cdc7d022849a6a279e91f31788c989d68377dc28c6f0
Detection
ClamAV: Win.Trojan.Agent-6943819-1
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln
embedded_office_0000660a_1.exe embedded-pe Office MZ+PE at offset 0x660A 292634 bytes
SHA-256: 2233af523fd64cba4c639f8a8c101624c5fcfee54cef9958247965002c28ed9f
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln
embedded_office_off0005086b.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x5086B 318756 bytes
SHA-256: aa7f3fc737cb3075ff4e920b56978193a5ce441b371709fe360edb1909f4aca2
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln
embedded_office_off00053e70.ole embedded-office Embedded OLE/CFB Office body inside ole container at offset 0x53E70 304927 bytes
SHA-256: 22ddc6a1220ba0d1fbf4ce366d2c964fa8bda69f05d69660ed8e43199051dd81
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln