Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 3a332f1b11c8801f…

MALICIOUS

RTF / .DOC

75.3 KB First seen: 2024-06-03
MD5: 79b8cf99303217fe4f267ba133e54c1e SHA-1: 32b19642fd76fb71c64bf73cd2ff5bb993a6c0a5 SHA-256: 3a332f1b11c8801f0197a99e8a6984c0fe2cafa0a68d75d4779b9e9e875d55e8
140 Risk Score

Malware Insights

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

The sample is an RTF document exploiting a known vulnerability in the Equation Editor (RTF_EQUATION_EDITOR, RTF_OBJUPDATE). The document body contains a lure instructing the user to 'Enable editing', which is a common tactic for macro-based malware or exploit documents. The embedded OLE object data further supports the exploit vector.

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_off0000311b.bin
15c917a56430c97b75794d85edf8f9245bc52db2ab980761ab01da553a636fcc
rtf-objdata-decoded RTF \objdata at offset 0x311B 1784 bytes