Malicious RTF — malware analysis report

Static analysis result for SHA-256 673ac11d7a40a868…

MALICIOUS

RTF

9.1 KB First seen: 2018-06-14
MD5: f2aa8972a64b000a186b074c3043d122 SHA-1: 425711de383b6a9e60490611fb1eda0a249949b0 SHA-256: 673ac11d7a40a86892d097f71d3ee757eae546ad89f782f5060e638ef1d200f2
220 Risk Score

Malware Insights

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

The sample is an RTF document containing embedded OLE object data, specifically triggering heuristics related to Equation Editor exploits and OLE activation. ClamAV identifies this as Rtf.Exploit.CVE_2017_11882-6584355-1, indicating a known vulnerability exploitation. This pattern suggests the file is designed to deliver a malicious payload via an attachment, likely through spearphishing, by exploiting the Equation Editor vulnerability to achieve client execution.

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_off0000003b.bin rtf-objdata-decoded RTF \objdata at offset 0x3B 4643 bytes
SHA-256: 03db2b763d06f6a76f48ced15c1dcef3a085cf4c0a5a6912fa95993a8b16e181