Malicious RTF — malware analysis report

Static analysis result for SHA-256 8972f88f545848ef…

MALICIOUS

RTF

43.5 KB First seen: 2023-08-03
MD5: 74d2ee93961c4db83a6255f428022d4e SHA-1: f527297e2c07efe57704c0520780f831513c46d5 SHA-256: 8972f88f545848efde365259eb058edea0d7db003df9d83d4696ecdaf7618bcc
180 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object specifically targeting the Equation Editor, a known vulnerability vector. The 'SE_ENABLE_LURE' heuristic indicates the document prompts the user to enable editing, which is a common social engineering tactic to bypass security measures. This suggests the file is designed to exploit the Equation Editor vulnerability to download and execute a malicious payload.

Heuristics 5

  • 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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off0000348a.bin
e79f63bdbd503c60c125ca64b4f093c71c6a347a1bc90ca5645fe0a242a59198
rtf-objdata-decoded RTF \objdata at offset 0x348A 1332 bytes