Malicious RTF — malware analysis report

Static analysis result for SHA-256 6b62a57ec7a1e739…

MALICIOUS

RTF

69.0 KB First seen: 2023-08-09
MD5: 86588b34f68fad2817ac9c8b7eee8568 SHA-1: 59aa9c71fe3421e2134e57ce6ac0d67034ff9d1b SHA-256: 6b62a57ec7a1e73957db53f846dd364108781a6464d4d800470c2c6d17614115
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 RTF file contains OLE object data and specifically targets the Equation Editor, a known vector for exploits. The \objupdate directive forces OLE activation, and the document includes a lure to enable editing, indicating an attempt to exploit a vulnerability. This combination strongly suggests a malicious document designed to execute arbitrary code via the Equation Editor vulnerability.

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_off00003fa1.bin
331b94c4a11960b8051195fb0e354fc4e69a7b994fc7ab383dbb5942d08c5285
rtf-objdata-decoded RTF \objdata at offset 0x3FA1 1773 bytes