Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 26dc56dbddfa9bc6…

MALICIOUS

RTF / .DOC

2.12 MB
MD5: f116645ace066e5ee2a4439a8e9788b6 SHA-1: 1e84876833a5cb4ceb98424601a0fedb0dda6808 SHA-256: 26dc56dbddfa9bc6579031c4452ea30adf1894300347df4830b2291f9c176b94
140 Risk Score

Malware Insights

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

The critical RTF_EQUATION_EDITOR heuristic indicates a likely exploit targeting the Equation Editor component. The presence of OLE object data and the ".objupdate" call further suggest that embedded objects are being activated to trigger malicious code execution. The embedded script content, though obfuscated, appears to contain functions for handling hexadecimal data and potentially redirecting the user's browser, indicating a downloader or exploit delivery mechanism.

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.
  • \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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000ded.bin
e5ed8aca0ec2c90362b422cd0d3e8c98fd9c9b87b5fb77ceed648e345017f57b
rtf-objdata-decoded RTF \objdata at offset 0xDED 56950 bytes
objdata_01_off00032a33.bin
975d3a2f2f8b7195d4eb809b2a138db9dd3913fc730826171b11bd21fa93d9f8
rtf-objdata-decoded RTF \objdata at offset 0x32A33 478829 bytes