Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 74ab7164330c640e…

MALICIOUS

RTF / .DOC

33.7 KB First seen: 2023-03-27
MD5: 3598624bc0b493794d01a351110da247 SHA-1: 2a6f882b14608c633acaf62f94ed33f648b931e0 SHA-256: 74ab7164330c640ea03e184339b6a3ed1be1c822cbdceeac2d2e0017f34c0045
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, and an \objupdate directive that forces OLE activation. The document body includes a lure instructing the user to 'Enable editing', indicating a social engineering attempt to bypass macro security settings and trigger an exploit. The specific exploit targeted is likely related to the Equation Editor vulnerability.

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 1 \objdata section(s) — embedded OLE objects
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000518d.bin
a7227744a1d1755078677ae6bb79af8849676263457b28ab600b27b124ee55b2
rtf-objdata-decoded RTF \objdata at offset 0x518D 1810 bytes