Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 3687f2ed161b33f5…

MALICIOUS

RTF / .DOC

1.49 MB
MD5: 33ce04c3aaff4168b756498f34429eaf SHA-1: 8d2526c297d691bf04cc1a3b3add8e2303841cdf SHA-256: 3687f2ed161b33f5c9dba06ac1bc784f15a83c353a594d2cf9724bcb6f9c56ff
140 Risk Score

Malware Insights

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

The critical RTF_EQUATION_EDITOR heuristic indicates the file exploits a known vulnerability in the Microsoft Equation Editor component. The RTF_OBJUPDATE heuristic suggests that the embedded OLE object is designed to be activated, likely triggering the exploit. The presence of OLE object data and embedded objects further supports this. The document body contains obfuscated JavaScript-like code which, combined with the exploit, likely serves to download and execute a secondary payload.

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_off000011df.bin
94225ff34718d27455297165341ae61bf09ea0026963f37977c303a559ed0dec
rtf-objdata-decoded RTF \objdata at offset 0x11DF 54798 bytes
objdata_01_off000321e1.bin
d2d324e28f9f3abf7d31268816f242dc5b73a8f28b0fbb08fc6be0000c82040f
rtf-objdata-decoded RTF \objdata at offset 0x321E1 322519 bytes