Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 730d905447a0ecde…

MALICIOUS

RTF / .DOC

67.6 KB First seen: 2023-09-19
MD5: 2bc2dfb3239184145052bd681d770246 SHA-1: f8525b5625359aff514f9887be92d3e85d673215 SHA-256: 730d905447a0ecde0d2460315f70588922508fac7e03c9368878929cf1b431fe
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 file 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 auditing to encourage users to enable editing, which would likely trigger the exploit. The presence of ".objdata" and ".objupdate" sections strongly suggests an attempt to execute embedded malicious content.

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_off00002a5c.bin
855a1ef1f2549920f3d617708cf876f99fc647a5a4bff876e356177ec6847c29
rtf-objdata-decoded RTF \objdata at offset 0x2A5C 1588 bytes