Malicious RTF — malware analysis report

Static analysis result for SHA-256 e102e0b552181fb8…

MALICIOUS

RTF

5.6 KB First seen: 2018-03-04
MD5: 3a34ed7f575900e1d37686aba140b6fc SHA-1: db90f029d8e3680b2c50cc928fc30512b9e3b0b4 SHA-256: e102e0b552181fb8cb346c4fda126a1e917b83dfbf8a74a2e5102dba9c65dbf4
222 Risk Score

Malware Insights

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

The RTF file contains an OLE object that is automatically linked and updated, exploiting CVE-2017-0199. This vulnerability allows the file to download a secondary payload from the embedded URL http://192.168.159.132/logo.txt, which is then likely executed on the victim's machine. The ClamAV detection further confirms the malicious nature of this exploit.

Heuristics 6

  • CVE-2017-0199 (OLE2Link / remote URL Moniker) critical CVE likely CVE_2017_0199
    RTF contains a URL Moniker OLE link whose decoded target is remote. Office can fetch and process the response through the CVE-2017-0199 OLE2Link attack path, but the server-side content type is not proven statically.
  • ClamAV: Rtf.Exploit.CVE_2017_0199-6335035-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2017_0199-6335035-0
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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 URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://192.168.159.132/logo.txt In RTF body
    • http://schemas.microsoft.com/office/word/2003/wordmlIn RTF body

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000001a2.bin rtf-objdata-decoded RTF \objdata at offset 0x1A2 2601 bytes
SHA-256: af2b489d34db030d27675b7410c06a6d9cfd23567814e0cdb36c0743e3c6eb52