Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 7a5a74a196e5b741…

MALICIOUS

RTF / .DOC

255.9 KB Created: 2019-08-06 01:42:00
MD5: 8caea5d87bc867e801327b66c2074975 SHA-1: be12803f8287e117839b5e8381454742b8bf4aa3 SHA-256: 7a5a74a196e5b7412a1e5304fed28c46d2b1ed85063a715c76f71537b2e1288e
142 Risk Score

Malware Insights

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

The sample is an RTF document containing an embedded OLE object that exploits the CVE-2017-11882 vulnerability in Microsoft Equation Editor. This vulnerability allows for arbitrary code execution, likely to download and execute a second-stage payload from the unknown URL. The document body is minimal and does not provide further context.

Heuristics 5

  • 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.
  • \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 3 \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://s249434.smrtp.ru/a/dar.msi
    • http://schemas.microsoft.com/office/word/2003/w

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000079f3.bin
3dd4060b593ee339bfde6b22afc402ec2b4c834fb1fae2429732cfa761a9fbf5
rtf-objdata-decoded RTF \objdata at offset 0x79F3 15892 bytes