Malicious RTF — malware analysis report

Static analysis result for SHA-256 54dcb86cd7a9cd21…

MALICIOUS

RTF

557.8 KB Created: 2019-01-23 19:55:00 First seen: 2019-09-30
MD5: 179051e8be7b3b96decc5893b077e924 SHA-1: 6169174d6f39f7499c44a21e500888db2c4c27b8 SHA-256: 54dcb86cd7a9cd21840b6bf9ec7a3923901c2289c1b498e4fbc78868e16a95a3
182 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The RTF document contains OLE object data and triggers OLE activation via \objupdate, indicating an attempt to exploit embedded objects. Critical heuristics identify CVE-2017-8759 and suspicious shellcode-related artifacts, including API strings and a URL. This suggests the file is designed to exploit this vulnerability to download and execute a secondary payload.

Heuristics 5

  • CVE-2017-8759 — MSXML SAX OLE activation critical CVE likely CVE_2017_8759
    RTF contains a hex-encoded OLE1 object for Msxml2.SAXXMLReader.6.0 followed by an embedded OLE compound document, and the document requests OLE activation. This matches the RTF staging shape used for CVE-2017-8759 SOAP/WSDL parser code injection.
  • Suspicious extracted artifact critical EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • \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://schemas.microsoft.com/office/word/2003/wordml In RTF body
    • https://bit.ly/2EuW1GWIn RTF body

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00074c9d.bin rtf-objdata-decoded RTF \objdata at offset 0x74C9D 1262 bytes
SHA-256: ba8acac4909b07e14e9120760ae48af756e704255e15e70d6a284015fa93072c
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered URL(s): https://bit.ly/2EuW1GW Static shellcode analysis found candidate code region(s). Indicators: SC_STR_LOADLIBRARY, SC_STR_URLDOWNLOAD, SC_PEB_ACCESS Static shellcode analysis recovered API/import strings: LoadLibraryA, GetProcAddress, URLDownloadToFileA, CreateProcessA, ExitProcess