Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 d8fa10d686fb89d6…

MALICIOUS

RTF / .DOC

364.0 KB
MD5: 9bfcc68a44a2cf6c3a27c5749f360e32 SHA-1: 23ceca88d35125b79880a06ea11b095fc4d5c0cb SHA-256: d8fa10d686fb89d62493a8d1b0f59caefc2da5fdb327b6a65c1ddd65f4c10944
122 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.003 Windows Command Shell

The RTF file contains an embedded OLE object that decodes to a PE file, indicating a likely exploit targeting the Equation Editor vulnerability. The presence of \objdata and \objupdate heuristics further supports the exploitation of OLE object data. The decoded object is likely a second-stage payload, though no specific family is identifiable from the static analysis alone.

Heuristics 4

  • 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_off0000005e.bin
f244efb737f0698a7c88dbdf8b3a92d37249f175a434c18bba71305f2b1a0933
rtf-objdata-decoded RTF \objdata at offset 0x5E 186224 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.