Malicious RTF — malware analysis report

Static analysis result for SHA-256 266a429f697c7230…

MALICIOUS

RTF

259.2 KB Created: 2021-02-12 04:30:00
MD5: e6869a9937aba06b8fe5beaf7bef531a SHA-1: f117e58b45bf4b7979f564350bdb5657269e6ea5 SHA-256: 266a429f697c7230c5c0de6445e89923a7349cbbe19e3f30afc6cdf66b17e998
142 Risk Score

Malware Insights

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

The sample is an RTF document that contains an embedded OLE object, specifically triggering the CVE-2017-11882 vulnerability in the Equation Editor. This exploit is known to facilitate arbitrary code execution. The document body content appears to be a list of schools, which is likely a lure to disguise the malicious intent of the embedded exploit. No scripts were extracted, but the exploit itself is sufficient to indicate a high likelihood of payload delivery.

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 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://schemas.microsoft.com/office/word/2003/wordml

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000106.bin
6f2546660c8101ee0d9e665b909f246ad752d2bccf8a495e5f3cd8f35d9fe6fe
rtf-objdata-decoded RTF \objdata at offset 0x106 3628 bytes