Malicious RTF — malware analysis report

Static analysis result for SHA-256 2b95254a16a36541…

MALICIOUS

RTF

8.3 KB First seen: 2019-05-31
MD5: 3932783a9da5509a813a1d9866ccfaf9 SHA-1: 80dfc121a9c104e98378c43e9f150ff005c67db7 SHA-256: 2b95254a16a36541c577dd71cab272ffea9b2ac36765ee381e9ceb65fe0e6386
240 Risk Score

Malware Insights

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

The RTF file contains embedded OLE object data and specifically triggers heuristics for CVE-2017-11882, indicating exploitation of the Equation Editor vulnerability. This vulnerability allows for arbitrary code execution, likely to download and run a secondary payload. The file is classified as malicious due to this exploit.

Heuristics 5

  • Equation Editor CLSID critical CVE likely RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • CVE-2017-11882 — Equation Editor FONT record overflow critical CVE likely CVE_2017_11882
    Equation Editor MTEF contains an overlong FONT typeface field, the vulnerable copy primitive for CVE-2017-11882. This is stronger evidence than the Equation Editor CLSID alone because it identifies the malformed record that drives code execution in EQNEDT32.EXE.
  • ClamAV: Doc.Exploit.CVE_2017_11882-6934206-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Exploit.CVE_2017_11882-6934206-0
  • \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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000032.bin rtf-objdata-decoded RTF \objdata at offset 0x32 4145 bytes
SHA-256: c93ac814d453f71a712fc9d81168a073a1545257dd3272375cd62621f4ac3a9b