Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 4993674dd160e929…

MALICIOUS

RTF / .DOC

3.9 KB First seen: 2021-09-29T12:13:56+00:00
MD5: d72a7776926c3a803d5fdd9d29c0207c SHA-1: 42c863a94ad8b05b8e73f6cb3a51c0ab32f07413 SHA-256: 4993674dd160e9290748d6fc1fab8bdcb8bf1fe08ede33ce5b1f8471f0e0db01
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The RTF document contains embedded OLE object data and triggers an ".objupdate" command, indicating an attempt to exploit the Equation Editor vulnerability. This technique is commonly used to achieve arbitrary code execution. The file's SHA256 hash is provided as a primary indicator.

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_off000000ca.bin
479012c1de33bb82f21ae9aeca0b9541001f81d1d40c77f6b5838226c9443531
rtf-objdata-decoded RTF \objdata at offset 0xCA 1721 bytes