Malicious RTF — malware analysis report

Static analysis result for SHA-256 51ecd503ede3dff0…

MALICIOUS

RTF

11.6 KB First seen: 2018-07-23
MD5: bdf5ea70aa38ebb0c7260014d08ba05c SHA-1: 7c0f2db1cfbc75afe197a92219237651338b6c70 SHA-256: 51ecd503ede3dff04e7cdb490a5be26fdc7732ff289cc59cf7203026f8ab77eb
220 Risk Score

Malware Insights

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

The file is an RTF document containing OLE object data, specifically triggering heuristics related to the Equation Editor vulnerability (CVE-2017-11882). This vulnerability is known to allow for arbitrary code execution. The ClamAV signature further confirms the exploitation of this CVE. The presence of OLE object data and the specific CVE exploit indicate the document's primary purpose is to compromise the user's system, likely by downloading and executing a secondary malicious payload.

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
  • Ole10Native stream in RTF OLE object high CVE related RTF_OLE10NATIVE_STREAM
    RTF contains an embedded OLE object with an Ole10Native stream. This is a strong payload-container signal and is related to Word/OLE exploit delivery, but it is not specific enough on its own to assign a CVE.
  • ClamAV: Rtf.Exploit.CVE_2017_11882-6584355-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2017_11882-6584355-1
  • \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_off00000a2c.bin rtf-objdata-decoded RTF \objdata at offset 0xA2C 4642 bytes
SHA-256: 1478eda726181ef473e6a34103c29ba4dba756330bdd36a9b923b31cbaa230f8