Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 82a32aee720b4bb6…

MALICIOUS

RTF / .DOC

16.1 KB First seen: 2022-10-26
MD5: 6cd937604f691ddfa441abdc2ab61f10 SHA-1: 0faf7f525d69b533d7e8fdef767c6e2a602154be SHA-256: 82a32aee720b4bb6279b7169622040ebbbc11301a059f223d63509991a27ad74
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The sample is an RTF document that contains an embedded OLE object. Heuristics indicate a critical vulnerability, CVE-2017-11882, related to the Equation Editor. This vulnerability is known to be used for arbitrary code execution, likely to download and run a second-stage payload. The RTF object data was extracted and decoded, but the content is heavily obfuscated and does not provide further direct clues about the payload.

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.
  • 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
  • \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_off00001c15.bin
0949115cf9f8c79baaaa7fdfbe87c3edaaa7659c34c1225d477af5caf006f865
rtf-objdata-decoded RTF \objdata at offset 0x1C15 4652 bytes