Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 fce04ed3fa9f8490…

MALICIOUS

RTF / .DOC

4.1 KB First seen: 2022-03-21
MD5: eb031583d1764be1d6b554c6427e1d65 SHA-1: 6cbc1eff1add9ba7cafaf1eb8a874100ba49c525 SHA-256: fce04ed3fa9f849041a08da34651e7209136f93729c5223cae80136bf1e5727e
121 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1559.002 Component Object Model Hijacking

The RTF document contains embedded OLE objects, specifically triggering critical heuristics related to the Equation Editor vulnerability. The presence of \objupdate further indicates an attempt to force OLE activation, leading to the exploitation of a client-side vulnerability for code execution. No specific malware family was identified, but the attack pattern is consistent with exploiting the Equation Editor.

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_off000000aa.bin
74f2b666007fa1bf62ed9b31983905b8517404296618cddfcd2b106c3fff29fa
rtf-objdata-decoded RTF \objdata at offset 0xAA 1811 bytes