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

Static analysis result for SHA-256 1a1cfde34918b3a0…

MALICIOUS

Office (OLE)

954.3 KB Created: 2003-07-13 10:04:24 Authoring application: Microsoft Excel First seen: 2019-04-18
MD5: 818c29b202a44002ddf98d8a7d31a2d2 SHA-1: aee61c8d5752d7825a30b5b5bf123bb1cac22222 SHA-256: 1a1cfde34918b3a0ec082f1772ee9bdeaf0c0b026d68e4b0d6e547d3aaf4b50f
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 977,175 bytes but its declared streams total only 12,288 bytes — 964,887 bytes (99%) 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 951053 bytes
SHA-256: 3925c6a3644e76c447b9960c22e5f92a03c781d420edbb2f261269003449835c
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 963346 bytes
SHA-256: dbf7cee4a63ea57345e1e56806f81729a74455069ddda5c053e98f505d7dd2e9
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 951447 bytes
SHA-256: 74acbbbc29ed9f9ee1d4bc74563f71ab49ff33eb24f7f226ccfbe36b1d4c3ad6
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 621218 bytes
SHA-256: c9944e2e82bf04ddf5562f4d5aeaaafb3d6a26810a6fd30ef75f39499f859b9b
Detection
ClamAV: Win.Trojan.Agent-6943819-1
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 647340 bytes
SHA-256: 1749426c776f3f66b870645fce42bf4ef904030709326e35e39156ad40db8c75
Detection
ClamAV: Win.Trojan.Agent-6943819-1
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 633511 bytes
SHA-256: fc5eacc7884dd3c8df23307f7d36233941e930bbcb32f8d4fad8cb0661e72da8
Detection
ClamAV: Win.Trojan.Agent-6943819-1
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): cmdln