Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 1276bfb8370c2f47…

MALICIOUS

Office (OOXML)

26.0 KB Created: 2019-08-30 09:39:00 UTC Authoring application: Microsoft Office Word 12.0000 First seen: 2020-02-04
MD5: ae571e035b3480f328db6bf66b38ce69 SHA-1: 139c1b2fc829617ad3ff5d85dc6e5e42f5aee2ee SHA-256: 1276bfb8370c2f471df1381e515c6096713d402d1f61678c24ddf5daf7528334
404 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.003 Windows Command Shell T1059.007 JavaScript T1105 Ingress Tool Transfer

The document contains a malicious DDE AUTOEXEC command that leverages cmd.exe and powershell.exe to download and execute a JavaScript file from 'http://23.106.123.105/Crypted.js'. This JavaScript then downloads and executes a Windows executable from 'http://45.11.19.145/mswiner.exe'. The presence of DDE commands and the multi-stage download and execution chain strongly indicate malicious intent.

Heuristics 10

  • ClamAV: Doc.Exploit.DDEautoexec-6346603-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Exploit.DDEautoexec-6346603-1
  • Field QUOTE with ASCII-integer command payload critical OOXML_FIELD_QUOTE_ASCII_PAYLOAD
    QUOTE field in word/document.xml carries a decimal-ASCII byte sequence that decodes to a shell command referencing cmd
  • Malicious DDE command critical OOXML_DDE_MALICIOUS
    DDE field in word/document.xml launches a dangerous executable: \\System32\\cmd.exe
  • Ole10Native package payload is a download-and-execute script critical OFFICE_PACKAGE_SCRIPT_DROPPER
    The OLE Package's embedded payload contains a script that hosts a shell (PowerShell/WScript/mshta), fetches a remote resource, and executes it — a download-and-run dropper. Embedding such a script inside an Office document via the Object Packager is a direct user-execution delivery technique (MITRE T1204.002), not a benign attachment.
  • Ole10Native package drops an auto-executable payload critical OFFICE_PACKAGE_RISKY_FILE
    OLE Package displayName or fullPath ends in a directly auto-executable extension (a runnable binary or a script the default shell host runs on double-click). Embedding such a payload inside an Office document has no benign authoring use — it is a malware-delivery dropper.
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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.
  • Embedded OLE object medium OOXML_OLE_OBJECT
    Document contains an embedded OLE object
  • Payload URL recovered from embedded OLE object (1 URL) info OOXML_EMBEDDED_OBJECT_URL
    An embedded OLE object (xl/word/ppt embeddings) carries a next-stage download URL in its Ole10Native/Package stream — stored literally (incl. UTF-16) or base64-encoded — which the package-level URL sweep does not see. Surfaced as an IOC; self-validating (only real payload hosts).
  • 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://23.106.123.105/new.rtf In document text (OOXML body / shared strings)
    • http://23.106.123.105/Crypted.jsIn document text (OOXML body / shared strings)
    • http://45.11.19.145/mswiner.exeEmbedded OLE package script
    • http://schemas.openxmlformats.org/markup-compatibility/2006In document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/relationshipsIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/officeDocument/2006/mathIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawingIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/wordprocessingml/2006/mainIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2006/wordmlIn document text (OOXML body / shared strings)

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
ooxml_oleobject_00.bin ooxml-ole-object OOXML embedded OLE part: word/embeddings/oleObject1.bin 5120 bytes
SHA-256: e9eba6aa0a21b4b41d6c78bde89b977508091fae2e99206120eff0dbcded045b
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): WScript.Shell',
ooxml_oleobject_00_ole10native_00.bin ole-package OOXML word/embeddings/oleObject1.bin Ole10Native stream: Ole10Native 2135 bytes
SHA-256: 01d9f87bd531df7bded155ac91f4d2ea8b947875cfd1bbb983ed2006ccc7a9be
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered command string(s): WScript.Shell',
emf_00.emf ooxml-emf OOXML EMF part: word/media/image1.emf 5212 bytes
SHA-256: 04a2219b5978e9210bafaa31e3e2004c30924f5f3043232f33df94d83cf09a0e
emf_01.emf ooxml-emf OOXML EMF part: word/media/image3.emf 1352 bytes
SHA-256: 6618f42d72a90e245d2769e3d8481016acfaf97c301aa050f2fbbc8b6e2668fb