Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 e39f7a6a0d3fb6c7…

MALICIOUS

RTF / .DOC

39.8 KB First seen: 2023-02-21
MD5: de6bb2926e9739421103d3e62d7c73af SHA-1: 8361cc42db32e824fcd43c57ddb7999bf5bf0ddc SHA-256: e39f7a6a0d3fb6c7ea42d62fb3fb74dcfa3cb3e4ca4766239942fbdca03b2699
200 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 T1559 Component Object Model Hijacking T1559.001 Component Object Model Hijacking: Component Object Model

The RTF document contains an embedded OLE object specifically targeting the Equation Editor vulnerability (CVE-2017-11882). The document body includes a lure instructing the user to 'Enable editing', which is a common tactic to bypass macro security settings and trigger the exploit. The embedded object's class ID, 'EQuATion.3', is a strong indicator of this specific exploit.

Heuristics 6

  • Equation Editor activation — CVE-2017-11882 related high CVE related CVE_2017_11882_ACTIVATION_RELATED
    RTF decodes to an Equation.3 ProgID and requests OLE activation with \objemb plus \objupdate. This reaches the legacy Equation Editor attack surface used by CVE-2017-11882/CVE-2018-0802 documents, but the malformed MTEF/native payload needed for stronger attribution was not recovered.
  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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_off0000580d.bin
03c76bfc0865daa3c5301393552dcbd9ba77c806cf31d21224f7c940826cf298		 rtf-objdata-decoded RTF \objdata at offset 0x580D 1304 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.