Malicious RTF — malware analysis report

Static analysis result for SHA-256 eb2b50cb3f0a25e3…

MALICIOUS

RTF

8.4 KB First seen: 2019-08-04
MD5: cf72b841d06d3aa75bcedfe468d22b4f SHA-1: eff1a6875640b168e014c16691fbe313521c4733 SHA-256: eb2b50cb3f0a25e3f3a51811e7310459bb11931d6a8216ac67de193fbfbbb1e3
260 Risk Score

Malware Insights

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

The RTF file contains embedded OLE object data, specifically triggering the critical CVE-2017-11882 vulnerability within the Equation Editor component. This exploit is designed to achieve arbitrary code execution on the victim's machine, likely delivered via spearphishing. No specific family could be identified, but the exploit is well-known.

Heuristics 6

  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000032.bin rtf-objdata-decoded RTF \objdata at offset 0x32 4153 bytes
SHA-256: 8f236511e34e4f7d6801ff0f67f9edbb8523a9ce8de0397991a12d52beb8ffd2