Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 1c998448876aef0c…

MALICIOUS

RTF / .DOC

3.8 KB
MD5: f8c3ca44ca00084caa5c5bb04fca970d SHA-1: 692f1f5f663f4e1b5d0ae86de723feedad98e45c SHA-256: 1c998448876aef0c0bea2dbefd09004b89a950644ee8271e741e7ebaa0a2e06e
120 Risk Score

Malware Insights

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

The RTF document contains embedded OLE object data and specifically triggers the Equation Editor vulnerability. The ".objupdate" directive indicates that the embedded OLE object will be activated upon opening, leading to the exploitation of the Equation Editor. This is a common technique for delivering malicious payloads.

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_off000000a1.bin
b26385c4badcf0d5b22a651873472d51f615991e95786bb71e643860873dbabf
rtf-objdata-decoded RTF \objdata at offset 0xA1 1613 bytes