Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 8404d3dc32b0555b…

MALICIOUS

RTF / .DOC

26.4 KB First seen: 2023-02-24
MD5: 9438b01f1e855f29eaf97344c263aa5e SHA-1: 271427843c271f7d0a0c4e69517bd39df9693b75 SHA-256: 8404d3dc32b0555bc3b076d7fc080d2a341508b4a2c84805a1d5ffc0057e2b39
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious Link: Malicious File T1059 Command and Scripting Interpreter T1059.005 Command and Scripting Interpreter: Visual Basic

The sample is an RTF document that contains an embedded OLE object, specifically targeting the Equation Editor vulnerability. The document body provides a lure related to financial audits, instructing the user to 'Enable editing'. This combination strongly suggests an exploit attempt, likely 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 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_off00002890.bin
9c98dc075869a6a5c56dddf5b09b3e4d3aea761137d509124ae9e8362ac051f4
rtf-objdata-decoded RTF \objdata at offset 0x2890 1283 bytes