Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2d0993cfe3ef5139…

MALICIOUS

RTF / .DOC

3.8 KB
MD5: 78983739b0cffc70a07f957c91563e3c SHA-1: a9a016185ef204c3df3f5b9797418348fc5d7ea6 SHA-256: 2d0993cfe3ef5139c233c4dfcacb287a9b9c40f0c3df4cb2464fcdcba39828be
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains embedded OLE object data and specifically triggers the Equation Editor vulnerability. The presence of ".objupdate" indicates that the embedded object is designed to be activated automatically upon opening, leading to the exploitation of the Equation Editor. This is a common delivery mechanism for exploiting known vulnerabilities to achieve arbitrary code execution.

Heuristics 4

  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \objupdate forces OLE activation high RTF_OBJUPDATE
    RTF contains \objupdate — forces automatic OLE object instantiation when the document is opened, bypassing user interaction. Almost exclusively seen in Equation Editor exploit documents.
  • OLE object data medium RTF_OBJDATA
    RTF contains 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000000c9.bin
383484dccd1e55beee0ce669aed31aefb3b124eeb70e10f8b5d4d3c691035f13
rtf-objdata-decoded RTF \objdata at offset 0xC9 1745 bytes