Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 e2ccaaa5a7e51fbd…

MALICIOUS

RTF / .DOC

461.1 KB
MD5: a85f5fddea671eca50a102b5571590dc SHA-1: 3ca562809bfadbe2bc9e83120f060e8ddcbd7509 SHA-256: e2ccaaa5a7e51fbdf34dcdfa32ea67ce3ab3311fff52b904ab1bbd19cce6c018
222 Risk Score

Malware Insights

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

The sample is an RTF document that leverages the CVE-2017-11882 vulnerability through a malicious Equation Editor OLE object. This exploit is known to download and execute a secondary payload. The high entropy of the embedded object further suggests it is an executable payload. No specific family could be identified, but the delivery mechanism is clear.

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.
  • Automatically linked OLE object high RTF_OBJAUTLINK
    RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
  • \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_off000014e3.bin
596c98ae7525ae1d4d2ca5f2405821d5294fa1a2470d4d007061e7a898b402bc
rtf-objdata-decoded RTF \objdata at offset 0x14E3 233301 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.