Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 62ec107ea6d4ed40…

MALICIOUS

RTF / .DOC

3.6 KB
MD5: cbf62d784ba5cf3abac78bdeea7d6378 SHA-1: 812cd6a75a09eb54e44b2a5c7a496d5f2084e5f8 SHA-256: 62ec107ea6d4ed40169000475c64d2345895e48cc5ba557ced8971234a0c3b46
120 Risk Score

Malware Insights

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

The RTF document contains embedded OLE object data and specifically triggers the Equation Editor vulnerability. The ".objupdate" directive forces the activation of this embedded object, leading to the execution of arbitrary code. This is a common technique for delivering malicious payloads via document attachments.

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_off0000009c.bin
b84a32cb9db4c3795734554acd33e68c7cf4ec24f260cb323993638cb2e65b4c
rtf-objdata-decoded RTF \objdata at offset 0x9C 1543 bytes