Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 230f4505ad7562cc…

MALICIOUS

RTF / .DOC

13.2 KB
MD5: dfe6e5a9716394631b7f098f22c5d76a SHA-1: 436e624aa2a3931cd28683829e511cadd158d0b4 SHA-256: 230f4505ad7562cca72358dd27f3fd1f3ce4bf1474913b7c4589acdded64d425
120 Risk Score

Malware Insights

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

The sample is an RTF document that contains OLE object data and triggers an objupdate event, indicating an attempt to activate embedded content. The critical heuristic firing for RTF_EQUATION_EDITOR strongly suggests exploitation of the Equation Editor vulnerability (CVE-2017-11882). This vulnerability is commonly used to deliver secondary payloads. No document body text or scripts were extracted, limiting the ability to determine the exact payload or delivery mechanism.

Heuristics 3

  • 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.
  • \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_off000007df.bin
acafb30805a0cd57963885a217c326841973a70d0340a1a02c8369ca9be52f32
rtf-objdata-decoded RTF \objdata at offset 0x7DF 1535 bytes