Malicious RTF — malware analysis report

Static analysis result for SHA-256 8cdb891ac842d646…

MALICIOUS

RTF

64.9 KB First seen: 2023-08-09
MD5: f46867432dd7f3b315b6c29d52ed0edb SHA-1: 7fe27e797731e6fb03e87cf39b9dd974011b8102 SHA-256: 8cdb891ac842d6460bfa4132614dd084e690bf4a9160515fb0bdba5dc1f58992
160 Risk Score

Malware Insights

MITRE ATT&CK
T1204 User Execution T1204.002 Malicious File

The RTF file contains an embedded OLE object and specifically targets the Equation Editor, a known vector for exploits like CVE-2017-11882. The document body includes a lure instructing the user to 'Enable editing', which is a common tactic to bypass macro security and trigger the exploit. No scripts were extracted, and the embedded binary artifact was not analyzed for further malicious behavior.

Heuristics 5

  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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_off000027fe.bin
7edcfdb2fb9fa77f18634ef1ede2454dce752744274f97aa0cb44e31fb16659a
rtf-objdata-decoded RTF \objdata at offset 0x27FE 1645 bytes