Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 5d224d19c866e52e…

MALICIOUS

RTF / .DOC

417.3 KB
MD5: 9c785e0645f03f516d1b01613f4940cd SHA-1: d89b99c46f64826846fd6de7eab229039cb9b949 SHA-256: 5d224d19c866e52eb3e5151b5f13d6e42eb07bea506c88d29d33c562be8b61f2
182 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object that decodes to a Portable Executable payload, strongly indicating exploitation of CVE-2017-11882. The presence of ".objdata" and ".objupdate" directives further supports the malicious intent of activating and executing the embedded object. The extracted payload is likely a second-stage malware dropper.

Heuristics 5

  • 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
  • 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_off00000076.bin
28d41051565382df9c36da8abd5c86af9d9d6f6e2264247dd4a224d2c2f3fa97
rtf-objdata-decoded RTF \objdata at offset 0x76 213504 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.