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

Static analysis result for SHA-256 0431e845431419bd…

MALICIOUS

Office (OLE)

632.4 KB Created: 2003-07-13 10:04:24 Authoring application: Microsoft Excel First seen: 2019-05-16
MD5: 14970ce96c9e9e26b00510cac2d00b20 SHA-1: 56616c7d8c892b2cc44dc5d11ef7ab4d04d5134a SHA-256: 0431e845431419bdbc40e75c59f14eee365519486f44d7c2866923c2ef6ab0d2
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: Xls.Dropper.Agent-7067600-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Dropper.Agent-7067600-0
  • 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 647,590 bytes but its declared streams total only 12,288 bytes — 635,302 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 621468 bytes
SHA-256: 8454f4e5abb2e1d92504de74d65bb29ced748e549e8135b698440c658749009e
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 633761 bytes
SHA-256: 8ccde02eff9cce1b34f7f1e77524b42e5f2978d42d840f386356ae4696329d60
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 621862 bytes
SHA-256: 83c7cff0bcb42bf7fabe456cfc065aecc73a598b2df7921a1e8bd5bf8c087232
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 291633 bytes
SHA-256: a293c31b2000553333c16336010ac6f3e180f5525338a032efdc2430e487649a
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 317755 bytes
SHA-256: c582ea7e044ed2311f21241f43ed031f2493eefc84598005d2e2ee80772a31e9
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 303926 bytes
SHA-256: ed28e4f70497a7e116d3e84aed6cc37ab0397a39c43a326641d413483fd3f9b9
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln