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

Static analysis result for SHA-256 af27758daa8e3371…

MALICIOUS

Office (OLE)

632.3 KB Created: 2003-07-13 10:04:24 Authoring application: Microsoft Excel First seen: 2019-05-10
MD5: 441833a2ff3b89a1060f7edc2443f372 SHA-1: 04a1f62d8a9ed38a3584ff0c2db13b75692d0bc6 SHA-256: af27758daa8e3371e40c03beef064d9b5c40b173a799aa0bb8d1162f02d78799
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 647,468 bytes but its declared streams total only 12,288 bytes — 635,180 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 621346 bytes
SHA-256: ad3f0c29b19f1ef9bd18758e4bafccd38798a18d100dc8203f8794dea865cb0e
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 633639 bytes
SHA-256: 6f9f95838b9bd53fda839d35ea3714d5f18f130ab891191012df29a6b0a0a494
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 621740 bytes
SHA-256: 297c5a528c8b2c068325e6c86884646d6187c800c12aa692cab1ce9b88c49706
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 291511 bytes
SHA-256: efe5c1534d54aafa68a06ece897c7c335f6f662eb5c647e4165186f97975e3dc
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 317633 bytes
SHA-256: cc6797eab05d042758c1342d24b1640fdc18be9dfc3947bde6176711faccaf5d
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 303804 bytes
SHA-256: c768797191f6df0b382b90e6eba5ca7c7ac17a9362ced6573542df651f65e7c1
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln