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

Static analysis result for SHA-256 fd77f73f62d90c52…

MALICIOUS

Office (OLE)

632.2 KB Created: 2003-07-13 10:04:24 Authoring application: Microsoft Excel First seen: 2020-04-06
MD5: d75bb97dbcbdce2cbd35e65c3b7e8ad0 SHA-1: 7e021dbcf2a16c0349f6ab5433474818cd7190cc SHA-256: fd77f73f62d90c52e5bb73d5844ad1b5ce2918ed803f0f17ae4ee3942fdd5b73
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 647,349 bytes but its declared streams total only 12,288 bytes — 635,061 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
    This finding applies to a carved embedded Office document found at a nonzero offset inside the submitted file, not directly to the top-level document. 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 621227 bytes
SHA-256: c4dc59d4e9b4622b4a2c8083538a2e0ee49c4cefc098427bcaf3aff723167d6e
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 633520 bytes
SHA-256: c9e5c5ccfda127dd2649a6f6d7cc3904038d5cc1b172d765b9f28066524ec8d4
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 621621 bytes
SHA-256: 17c4f4bd23584f8ee98dd7a43a62349bdf0340388a1814251eb1149298b08bba
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 291392 bytes
SHA-256: 485f6bddb21c173f6ce411ee05123a5ed66617553cfd30dc6ca583949e240ce0
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 317514 bytes
SHA-256: 897c8c0338c310400a152e5b5563a8bdc6341b790137f6d8ecf1cab82d247c47
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 303685 bytes
SHA-256: fc0cb29b9274199a4f6580d713de05a15a214b6e96aef352ce276d17a2621e57
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln