Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 030e74c1f62bd15a…

MALICIOUS

RTF / .DOC

38.0 KB First seen: 2023-05-08
MD5: d94ad8cc32b6ec476dc1b58637eb3544 SHA-1: 5285f7c3bc2cba35aded0fe376f0808ab8af8373 SHA-256: 030e74c1f62bd15a50731f20049d0b8279bcd9ff1bb9d3fb1c0cfb643e317f80
120 Risk Score

Malware Insights

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

The sample is an RTF document that contains embedded OLE object data and specifically triggers heuristics related to the Equation Editor vulnerability. The ".objupdate" directive indicates that the embedded OLE object is intended to be activated automatically, which is a common technique for exploiting Equation Editor vulnerabilities to achieve arbitrary code execution. This likely leads to the download and execution of a secondary payload.

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 1 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000059e1.bin
9ab5c792e750ef6855db2b89b0eec6e5848777c38cb6006f9c0682922a712df6
rtf-objdata-decoded RTF \objdata at offset 0x59E1 1408 bytes