Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 7700f4ef78fb30aa…

MALICIOUS

RTF / .DOC

314.0 KB
MD5: 8ddb30bd470a26d8618a95eda466f4a2 SHA-1: 8275e288e6a3871a1970f1f1afaf3d1982c696cc SHA-256: 7700f4ef78fb30aac74964f4ef2f6653ca9eb14f55b5fd0012f4528dc6bed9b1
202 Risk Score

Malware Insights

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

The RTF document contains embedded OLE object data, specifically related to the Equation Editor. Heuristics indicate a critical vulnerability (CVE-2017-11882) was exploited, which is known to be used for delivering malicious payloads. An object was extracted which likely contains the second-stage malware.

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.
  • Decoded Equation Editor payload + PE critical RTF_EQUATION_EDITOR
    RTF decodes to an Equation Editor ProgID adjacent to OLE activation and the same decoded object stream contains embedded PE bytes. This matches the Equation Editor exploit surface used by CVE-2017-11882 / CVE-2018-0802 documents, while requiring payload evidence to avoid flagging benign Equation references.
  • \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
  • 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_off00001cb5.bin
1894d12109a918bc8b57709cf8e84519b5497dc3e4664f8802db240d3932bef0
rtf-objdata-decoded RTF \objdata at offset 0x1CB5 156903 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.