Malicious RTF — malware analysis report

Static analysis result for SHA-256 51d56ffa566a62da…

MALICIOUS

RTF

133.0 KB First seen: 2019-08-04
MD5: f17456098d7ba045ab62b9963d7dcca0 SHA-1: 927171f12b3f3711676c5d1717a97f3d4d9ff97f SHA-256: 51d56ffa566a62daa4f69033d8b4db0e66d6d3b5f958dd1ee3ddb82212a12ed5
160 Risk Score

Malware Insights

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

The RTF file contains OLE object data that is automatically linked and updated, triggering exploitation of CVE-2017-0199 or CVE-2017-8759. This vulnerability allows the embedded OLE object to act as a loader for a second-stage payload, likely downloaded from a remote source. The specific download URL or payload is not statically discernible, but the exploitation mechanism is clear.

Heuristics 4

  • CVE-2017-0199 / CVE-2017-8759 (OLE2Link auto-activated remote loader) critical CVE related RTF_OLE2LINK_REMOTE_MONIKER_LOADER
    RTF embeds an OLE2Link object that is force-activated with \objupdate (no user interaction on open) and fetches a remote second stage — through an INCLUDETEXT/INCLUDEPICTURE field or the OLE object's own moniker. This is the OLE2Link auto-update attack path shared by CVE-2017-0199 (server returns an HTA/scriptlet) and CVE-2017-8759 (server returns a SOAP WSDL the .NET parser compiles). Office processes the fetched response through the same code path; the specific CVE depends on the now-unreachable server content type.
  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0001b1b7.bin rtf-objdata-decoded RTF \objdata at offset 0x1B1B7 2637 bytes
SHA-256: 3a51f42c5071079b88e4549a408ee93f5db80da9339f11ff2a6fd44817188d0e

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