Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 1b6ee4cf21404aa0…

MALICIOUS

RTF / .DOC

39.3 KB First seen: 2023-05-15
MD5: 3983f69226c894d043f9962c860be01e SHA-1: 3b295b0d174fc01dbd125ec17b1718c80110b897 SHA-256: 1b6ee4cf21404aa05a7767386c8b70bb521dfd5ca4f5fd76780f4d252b087ce7
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1059.005 Visual Basic

The RTF document contains an embedded OLE object with a split Equation Editor ProgID, indicating an attempt to exploit the Equation Editor vulnerability. The presence of \objupdate suggests the object is designed to activate automatically upon opening. The document body contains a lure instructing the user to 'Enable editing', a common tactic to bypass security measures and trigger the exploit.

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_off0000531e.bin
2b6898a682e29e9cfae0811e21898e71ce55438e484b5a9f39b8b9c9ccd28868
rtf-objdata-decoded RTF \objdata at offset 0x531E 1694 bytes