Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 ae9f6a760fa801e2…

MALICIOUS

RTF / .DOC

4.1 KB First seen: 2022-06-09
MD5: 47216ac471239e795132879eebac9b20 SHA-1: c1524325ac67d0543cb1baef0fcff23288aefd92 SHA-256: ae9f6a760fa801e216482c7abbb6a61775cfe49fa4257544bf00e7a10488a77c
121 Risk Score

Malware Insights

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

The file is an RTF document that contains embedded OLE object data. Heuristics indicate a critical finding of a split hex Equation Editor ProgID and an OLE object, along with a high finding for \objupdate forcing OLE activation. This strongly suggests exploitation of the Equation Editor vulnerability (CVE-2017-11882) to achieve arbitrary code execution.

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_off0000005b.bin
663f689e6de68e0abce43f58649706f61e1d530fddb61df973807e94c1acc612
rtf-objdata-decoded RTF \objdata at offset 0x5B 1725 bytes