Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 0d2442d065ae3495…

MALICIOUS

RTF / .DOC

4.36 MB
MD5: c74b2ca44acace799c36dc9366e06c7c SHA-1: 4fa2e636dc1cdfa865bc75c373c4bff2a86a4157 SHA-256: 0d2442d065ae349595d99433a4370e3c40476e1ecfab4ce5278310a89a001d20
222 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object that exploits CVE-2017-11882, a known vulnerability in Microsoft Equation Editor. This exploit is designed to download and execute a secondary payload, indicated by the high entropy and large size of the extracted OLE object data. The presence of the Equation Editor ProgID 'EquatIon.3' further confirms the exploitation vector.

Heuristics 6

  • Equation Editor OLE1 native payload — CVE-2017-11882 related critical CVE related CVE_2017_11882_RELATED
    RTF decodes to an OLE1 Equation.3 embedded object whose native data is large and payload-like, and \objupdate requests automatic activation. This is the delivery shape used by Equation Editor RCE documents such as CVE-2017-11882/CVE-2018-0802, but the malformed MTEF record needed for exact attribution was not recovered.
  • Split hex Equation Editor ProgID + OLE object critical RTF_EQUATION_EDITOR
    RTF embeds the Equation.3 ProgID as hex bytes near OLE object activation and splits the byte stream with whitespace or an ignorable RTF group. This is an Equation Editor OLE activation surface commonly used by CVE-2017-11882 / CVE-2018-0802 exploit documents.
  • \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 ~4569KB of hex-encoded data inside \objdata sections — may hide a payload
  • 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_off00000043.bin
dd8a74d8fe6862060ec5a4c0acecae41e17bb845cb325e4dd08ff61e0dcebf8f
rtf-objdata-decoded RTF \objdata at offset 0x43 2285003 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.