Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 764754a4d7bdf067…

MALICIOUS

RTF / .DOC

32.3 KB First seen: 2023-02-15
MD5: cccf4483f22f181ce61c8361894ceb43 SHA-1: 1fd0bf825cd202c68a7e0d31214ab1fb1fc35dc8 SHA-256: 764754a4d7bdf0679886aa4f7ff9798f887cc352b8c58daf76790f63b89882ba
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution: Malicious Link T1059.005 PowerShell T1204.002 User Execution: Malicious File

The sample is an RTF document containing an embedded OLE object, specifically targeting the Equation Editor vulnerability. The document body includes a lure instructing the user to 'Enable editing', which is a common tactic to bypass security measures and trigger the exploit. The presence of \objupdate further indicates an attempt to automatically activate the embedded object, 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_off00005310.bin
ee240223bb0840016c1ade36010742fb16819f4e3b3aceec7df928bf99f1cf38
rtf-objdata-decoded RTF \objdata at offset 0x5310 1463 bytes