Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 b1ea4a9eaf3f5ada…

MALICIOUS

Office (OOXML)

799.8 KB Created: 2013-05-13 00:33:00 UTC Authoring application: Microsoft Office Word 14.0000 First seen: 2015-09-20
MD5: 4bc34385d03dba6335b18e1913d387c0 SHA-1: c545683e0947a14fe46c429223e0defe109114d9 SHA-256: b1ea4a9eaf3f5adae3f1c47d9cfa4a0fbc729ff02b008fa98b97ed33c73e5324
266 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1140 Deobfuscate/Decode Files or Information

The sample is a malicious Office document containing an embedded OLE object. This object is identified as a script dropper that combines network fetching and execution capabilities. It is configured to download and execute a file named AdobeReader.exe, indicating a downloader or dropper functionality. The ClamAV detection 'Doc.Dropper.Agent-5895440-0' further supports this assessment.

Heuristics 7

  • ClamAV: Doc.Dropper.Agent-5895440-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Agent-5895440-0
  • 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.
  • Embedded OLE object medium OOXML_OLE_OBJECT
    Document contains an embedded OLE object
  • Payload URL recovered from embedded OLE object (5 URLs) 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).
  • Suspicious extracted artifact info 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 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.thawte.com0 Embedded OLE package script
    • http://ts-ocsp.ws.symantec.com07Embedded OLE package script
    • http://schemas.microsoft.com/office/word/2010/wordprocessingCanvasIn document text (OOXML body / shared strings)
    • 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.microsoft.com/office/word/2010/wordprocessingDrawingIn 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/2010/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingGroupIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingInkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2006/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingShapeIn document text (OOXML body / shared strings)
    • http://crl.thawte.com/ThawteTimestampingCA.crl0Embedded OLE package script
    • http://ts-aia.ws.symantec.com/tss-ca-g2.cer0Embedded OLE package script
    • http://ts-crl.ws.symantec.com/tss-ca-g2.crl0Embedded OLE package script
    • http://ts-crl.ws.symantec.com/tss-ca-g2.crl0(In document text (OOXML body / shared strings)

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
ooxml_oleobject_00.bin ooxml-ole-object OOXML embedded OLE part: word/embeddings/oleObject1.bin 649216 bytes
SHA-256: cd276b4f31b927f4799335eb15f4327993755b7e6048016caa79b7cf4a95b10f
Detection
ClamAV: Doc.Dropper.Agent-5895440-0
Obfuscation or payload: likely
Carved artifact entropy is 7.86, consistent with packed or encrypted content.
ooxml_oleobject_00_ole10native_00.bin ole-package OOXML word/embeddings/oleObject1.bin Ole10Native stream: Ole10Native 642048 bytes
SHA-256: bc8312fc3c4784d04a9c22eb65254d13ac4459df2359eab838f4b4e3927e86b9
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.87, consistent with packed or encrypted content.
emf_00.emf ooxml-emf OOXML EMF part: word/media/image1.emf 5156 bytes
SHA-256: e3fedb36638dcfc93d31c78323357887e8688e5aa4c7f8296d4dd4af4013b2cd