Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 29543b9b76ebe822…

MALICIOUS

RTF / .DOC

27.9 KB First seen: 2023-03-20
MD5: e9155f72e05c2026e43f41bc37dba8e4 SHA-1: 1eda20b8b000273a1a72ba329705b3022e640353 SHA-256: 29543b9b76ebe822d821594bd3aba8b04ddd03c51d922ccedcb7fb9f1bb3c880
140 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object with an Equation Editor ProgID, triggered by \objupdate, which is a known exploit technique. The document body includes a lure instructing the user to 'Enable editing' to view the content, indicating a social engineering attempt to bypass macro security settings and activate the exploit.

Heuristics 4

  • 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
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000525c.bin
813d4f6ad45c579c01edb590384b5d33baa395b1e5cd4391b2015f78da345b4b
rtf-objdata-decoded RTF \objdata at offset 0x525C 1507 bytes