Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 5c783a84eb7784cc…

MALICIOUS

RTF / .DOC

1.87 MB
MD5: c37d902c03a12a87e5394f849ae966d3 SHA-1: 8b4a32210a84fe179b97b211e05bccec0a377789 SHA-256: 5c783a84eb7784ccab875c4ec73f44f99a6e443ef7c5dcfaaaa9f2e23f71e072
340 Risk Score

Malware Insights

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

The RTF file contains multiple indicators of exploitation targeting Microsoft Equation Editor, specifically identified as CVE-2018-0802. The presence of OLE object data, automatic linking, and excessive hex-encoded data strongly suggests the file is designed to deliver a malicious payload via this vulnerability. The ClamAV detection further confirms the exploit's presence.

Heuristics 8

  • Composite Moniker in RTF OLE object high CVE related RTF_COMPOSITE_MONIKER_RELATED
    RTF contains Composite Moniker CLSID in OLE object context, but no nearby scriptlet/SCT payload was confirmed. Treat as related moniker attack-surface evidence rather than proof of CVE-2017-8570 exploitation.
  • Ole10Native stream in RTF OLE object high CVE related RTF_OLE10NATIVE_STREAM
    RTF contains an embedded OLE object with an Ole10Native stream. This is a strong payload-container signal and is related to Word/OLE exploit delivery, but it is not specific enough on its own to assign a CVE.
  • Equation Editor CLSID critical RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • ClamAV: Rtf.Exploit.CVE_2018_0802-6825822-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2018_0802-6825822-0
  • 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.
  • Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX
    RTF contains ~1937KB of hex-encoded data inside \objdata sections — may hide a payload
  • OLE object data medium RTF_OBJDATA
    RTF contains 2 \objdata section(s) — embedded OLE objects

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000000ab.bin
4fd209a23e989d9362ad43a4d1ed8773ad96247a921c078966eff89dc51e226b
rtf-objdata-decoded RTF \objdata at offset 0xAB 971111 bytes