Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 467ce2a90aee70f5…

MALICIOUS

RTF / .DOC

35.2 KB First seen: 2023-04-14
MD5: 4d03bdc3364af75b606c97c95628fcf5 SHA-1: 74a57c403f16f24eae977f9899d787e1f285124c SHA-256: 467ce2a90aee70f5bb08c494f6221b7f1abc3e63890fed0dea219902dd51ddb0
140 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.005 Service Execution

The sample is an RTF document containing an embedded OLE object with an Equation Editor ProgID, triggering heuristics for Equation Editor exploitation and OLE object activation. The document body contains a lure instructing the user to 'Enable editing', a common tactic for macro-based malware. The embedded OLE object is likely a weaponized component designed to trigger the Equation Editor vulnerability (CVE-2017-11882) for arbitrary code execution.

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_off00004793.bin
07c8a5a2459b526669090b977a2c33afa3672ba45db2c07e9e91a81a1e548d57
rtf-objdata-decoded RTF \objdata at offset 0x4793 1505 bytes