Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 0ee87c38a46c1e2c…

MALICIOUS

RTF / .DOC

9.2 KB First seen: 2022-03-14
MD5: afaba454894f4a81bd7bddab3deec9f2 SHA-1: f781efbf3b7270e429a79e7410db0b1c62a502e2 SHA-256: 0ee87c38a46c1e2c3e7d21e0108b12b78b2083eee3bb9beee031fcd6340d3632
120 Risk Score

Malware Insights

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

The sample is an RTF document that contains embedded OLE objects and triggers an Equation Editor exploit. The presence of \objupdate indicates that the embedded object is designed to be activated automatically, leading to code execution. This is a common technique for delivering malware via malicious documents.

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_off000012c1.bin
61744a1517c0d29c2668e62866098264db164c1dd9392b9e3d02914425c43a84
rtf-objdata-decoded RTF \objdata at offset 0x12C1 2057 bytes