Malicious RTF — malware analysis report

Static analysis result for SHA-256 3d683d5dd2c460b2…

MALICIOUS

RTF

261.1 KB Created: 2018-07-03 09:28:00 First seen: 2019-03-18
MD5: 66f36d6df952bd7f7a072310c28f4738 SHA-1: 68aa1efe3701397fc616d1e8cf7d5870602a597e SHA-256: 3d683d5dd2c460b203a339e4432d3ff7d65d7f2d22a8d47cb72a0c40a201e6c0
262 Risk Score

Malware Insights

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

The RTF document contains embedded OLE objects and triggers critical heuristics for CVE-2017-11882 (Equation Editor FONT record overflow) and CVE-2017-8759 (MSXML SAX OLE activation). These vulnerabilities are exploited to execute a malicious MSI installer hosted at http://schrott-stuttgart.com/.well-known/pki-validation//l/css/tate.msi, indicating a likely spearphishing attachment attack.

Heuristics 7

  • 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.Exploit.Cve_2017_11882-7570663-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Exploit.Cve_2017_11882-7570663-1
  • \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
  • 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://schrott-stuttgart.com/.well-known/pki-validation//l/css/tate.msi 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_off0000bf6b.bin rtf-objdata-decoded RTF \objdata at offset 0xBF6B 15672 bytes
SHA-256: 8492bdb97027837f5e624867f080504a54a1e0022d0a741c654413da607c1e3e

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