Malicious RTF — malware analysis report

Static analysis result for SHA-256 4e42238cb4b748dd…

MALICIOUS

RTF

11.6 KB First seen: 2019-04-18
MD5: d75d0f880981fc995d4b3a3f82ef4efb SHA-1: c296fa3e4842d89d3f12d4ac828180e9f6c77357 SHA-256: 4e42238cb4b748ddb12f0c199c9bbd4ec87d0b8e7c5724da25d2eafc34c049be
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_off00000a2b.bin rtf-objdata-decoded RTF \objdata at offset 0xA2B 4643 bytes
SHA-256: 1dcd94ef8d54cb2d1f720692324ce410e5277ce85d2715b1f244dacd4545ae54