Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 59143ce3ce84a082…

MALICIOUS

RTF / .DOC

4.7 KB First seen: 2022-05-12
MD5: a212761666e596995d242cebf5df8592 SHA-1: 1a89d483c3a0836446d7bcedfe72d09606b49a08 SHA-256: 59143ce3ce84a082ead015d3cca2fbf9bc7f15aaeb9785ca04dffe15227d716e
121 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains embedded OLE object data and specifically triggers the Equation Editor vulnerability. The \objupdate directive forces the activation of this embedded object, leading to the exploitation of the Equation Editor. This indicates a malicious document designed to execute arbitrary code via this known exploit.

Heuristics 3

  • 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 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000000ba.bin
7cd28f5acaeb952c32a0d0ca991f70f8d1b81efbf18b9e64318780eb3fcf75c5
rtf-objdata-decoded RTF \objdata at offset 0xBA 2059 bytes