Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 db95fdd4458a5adc…

MALICIOUS

RTF / .DOC

31.7 KB First seen: 2023-03-20
MD5: b4eed0d6dc956d9fc14886a6d4736d01 SHA-1: a461f7861b1d20c278457c5d43f203277bd427bd SHA-256: db95fdd4458a5adc40e303cdae4b77a55742d557258201ede0e0e9800f48d499
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution T1204.002 User Execution: Malicious File

The RTF document contains an embedded OLE object with an Equation Editor ProgID, and an \objupdate directive that forces OLE activation. This strongly suggests an attempt to exploit a known vulnerability, likely CVE-2017-11882, to execute arbitrary code. The document body's lure to 'Enable editing' further supports this attack vector.

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_off000059ad.bin
f59cf3ee68733f29ec43b2b2d630b37942e0df4eac63acd34c75f6ea2ddfe966
rtf-objdata-decoded RTF \objdata at offset 0x59AD 1747 bytes