Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 c06cf34b285f3885…

MALICIOUS

RTF / .DOC

25.7 KB
MD5: 4104f80e34ee3baf5b5090956c1c6edf SHA-1: 84a5be16666fa963d20ef5c2f2ff186ea5eff452 SHA-256: c06cf34b285f388588cb603efed0ed9b0b298aeceef632bf21839b22050e00e8
120 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, specifically targeting the Equation Editor vulnerability. The \objupdate directive forces OLE activation, indicating an attempt to exploit this vulnerability. This exploit is likely used to download and execute a second-stage payload, as suggested by the critical heuristic firing for Equation Editor exploitation. No specific malware family could be identified.

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_off00001fc8.bin
a2ea40da9d74a1b4dcf8ab6b756bca00cc4f2baecd14788152bd3e36b9b4682d
rtf-objdata-decoded RTF \objdata at offset 0x1FC8 1773 bytes