Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 cd651d4e8e5f9587…

MALICIOUS

Office (OOXML)

112.3 KB Created: 2019-05-25 04:16:00 UTC Authoring application: Microsoft Office Word 16.0000 First seen: 2020-12-01
MD5: 387c21ba850d0dcc3aa8efccc788b49b SHA-1: 0cbcf0a41acaf731a337a8c17e3f078cdb01ec23 SHA-256: cd651d4e8e5f9587f560a94c0a5ec6283938b906b4831341beb186eec11145cd
284 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File T1105 Ingress Tool Transfer

The sample is an Office document containing an embedded OLE object that functions as a dropper. This object is designed to download and execute a payload, identified as 'plugin.exe', from URLs such as http://crl.verisign.com/tss-ca.crl0. ClamAV detections confirm the malicious nature of the file and its extracted artifact, indicating it's a known dropper.

Heuristics 7

  • ClamAV: Doc.Dropper.Agent-7062511-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Agent-7062511-0
  • 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
  • Suspicious extracted artifact medium 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.
  • Payload URL recovered from embedded OLE object (11 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).
  • 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 Embedded OLE package script
    • http://ocsp.thawte.com0Embedded OLE package script
    • http://www.haozip.com/0In document text (OOXML body / shared strings)
    • http://www.haozip.com/In document text (OOXML body / shared strings)
    • http://www.haozip.comIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2010/wordprocessingCanvasIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2014/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2015/9/8/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2015/10/21/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/9/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/10/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/11/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/12/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/13/chartexIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/5/14/chartexIn document text (OOXML body / shared strings)
    • http://schemas.openxmlformats.org/markup-compatibility/2006In document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2016/inkIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/drawing/2017/model3dIn 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/2012/wordmlIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2016/wordml/cidIn document text (OOXML body / shared strings)
    • http://schemas.microsoft.com/office/word/2015/wordml/symexIn 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.verisign.com/tss-ca.crl0Embedded OLE package script
    • http://crl.verisign.com/ThawteTimestampingCA.crl0Embedded OLE package script
    • https://www.thawte.com/cps0Embedded OLE package script
    • http://crl.thawte.com/ThawtePremiumServerCA.crl0Embedded OLE package script
    • http://cs-g2-crl.thawte.com/ThawteCSG2.crl0Embedded OLE package script
    • http://crl.thawte.com/ThawtePCA.crl0Embedded OLE package script

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 148480 bytes
SHA-256: 0cce2993f8960cdceb2c38414a013d7e6d481ac7054818d39fde69c83919983e
Detection
ClamAV: Doc.Dropper.Agent-7062511-0
Obfuscation or payload: likely
Static shellcode analysis found candidate code region(s). Indicators: NOP sled, SC_PEB_ACCESS, SC_STR_SHELLEXEC Static shellcode analysis recovered API/import strings: shell32.dll, LoadLibraryA, GetProcAddress, CreateFileW, LoadLibraryW, VirtualAlloc
ooxml_oleobject_00_ole10native_00.bin ole-package OOXML word/embeddings/oleObject1.bin Ole10Native stream: Ole10Native 144484 bytes
SHA-256: 119b587d7fc2ead3b01e6085da74383aca8944509f1cdeb099e44ef4b439a476
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis found candidate code region(s). Indicators: NOP sled, SC_PEB_ACCESS, SC_STR_SHELLEXEC Static shellcode analysis recovered API/import strings: shell32.dll, LoadLibraryA, GetProcAddress, CreateFileW, LoadLibraryW, VirtualAlloc
ooxml_oleobject_00_ole10native_00_plugin ole-package-payload OOXML word/embeddings/oleObject1.bin Ole10Native payload: display_name=plugin; full_path=C:\Users\DELL_2~1\AppData\Local\Temp\plugin.exe; temp_path=; def_file= 144160 bytes
SHA-256: 5aee7ae5dd28fcd7e672912292061022c29538bf9264db56b30efdbc8d45abc0
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis found candidate code region(s). Indicators: NOP sled, SC_PEB_ACCESS, SC_STR_SHELLEXEC Static shellcode analysis recovered API/import strings: shell32.dll, LoadLibraryA, GetProcAddress, CreateFileW, LoadLibraryW, VirtualAlloc
emf_00.emf ooxml-emf OOXML EMF part: word/media/image1.emf 5140 bytes
SHA-256: 1da8b504db9d97c6f3c84925fbaf58f29baae1ab82571a85e7beb6bf784ab4ba