Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 a2a111ecec7bd8d7…

MALICIOUS

RTF / .DOC

409.1 KB
MD5: 247fbd575a2f1f57e8469cae4a4fa7d0 SHA-1: 2f65522d372795c3c36689333536f2ef43838464 SHA-256: a2a111ecec7bd8d7a7e422a0ffcdecdaa262f80bc3644e70ee76990d1511336f
122 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The sample is an RTF document that exploits the CVE-2017-11882 vulnerability in Microsoft Equation Editor. This vulnerability allows for arbitrary code execution when the embedded OLE object is activated. The extracted document body is heavily obfuscated and does not provide clear user-facing content, but the exploit itself indicates a malicious intent to compromise the user's system. The primary IOC is the file's SHA256 hash.

Heuristics 4

  • 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
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off00000d34.bin
d8c8e3c068b010690d1ea41741c8874990203d59d20fc953bce68e6729e5f546
rtf-objdata-decoded RTF \objdata at offset 0xD34 64068 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.93, consistent with packed or encrypted content.