Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 2ff6f8d15f65d5fa…

MALICIOUS

RTF / .DOC

25.4 KB First seen: 2022-10-13
MD5: 3f52923f3cf0a00970e0df3f999a815c SHA-1: d0094d2c80df9ededd9668abdb9b205cc7edecf7 SHA-256: 2ff6f8d15f65d5fa690f273ba140a47a6a3553effe28fb1bda92002e375a4c8e
140 Risk Score

Malware Insights

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

The file is an RTF document containing an embedded OLE object, specifically targeting the Equation Editor vulnerability (RTF_EQUATION_EDITOR). The presence of \objupdate indicates an attempt to force activation of this object. The document body contains a lure instructing the user to 'Enable editing', a common tactic to bypass macro security settings and facilitate exploitation.

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_off00000add.bin
ea038356b92e7262bb482e8348ba566fb6226fa3b821b0e51f6a34b39fb9e4eb
rtf-objdata-decoded RTF \objdata at offset 0xADD 1803 bytes