Malicious RTF — malware analysis report

Static analysis result for SHA-256 53d9739ed561caf0…

MALICIOUS

RTF

4.6 KB First seen: 2021-05-23
MD5: 8e0c57ff00ee5b81744a899672deb07a SHA-1: e52a9f4244b0bfcf16ffa98bfe3a2183972d9656 SHA-256: 53d9739ed561caf06675d79c7b970596905d499d916d5afcdf98e844717ecb82
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF file contains embedded OLE objects and specifically triggers the Equation Editor vulnerability. This indicates the file is designed to exploit a known flaw in Microsoft Equation Editor to achieve code execution upon opening. The presence of ".objupdate" further suggests an attempt to force the activation of the embedded OLE object, likely to trigger the 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_off000000ac.bin rtf-objdata-decoded RTF \objdata at offset 0xAC 2120 bytes
SHA-256: 9062b36fd66201bb5894d5e5fe83df94056f4410fdbd7dd9ecb9f9f036c4133c

Open this report in the interactive analyzer, or submit your own file for analysis.