Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 c7f0f932dd3637a4…

MALICIOUS

RTF / .DOC

4.31 MB
MD5: 24ed0fc97155eafbd19fb71b24339e4e SHA-1: d01d60d7c9aca1b93a9750c14a2ba980155aec24 SHA-256: c7f0f932dd3637a4260ec54380b34a438d5971bdf88048dda8587e800de610f7
222 Risk Score

Malware Insights

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

The RTF document contains an embedded OLE object specifically related to Equation Editor, triggering critical heuristics for CVE-2017-11882. The presence of a large, high-entropy extracted artifact within the OLE object strongly suggests it is a packed or encrypted payload. The objupdate directive further indicates an attempt to automatically activate the embedded object, likely leading to the execution of the exploit.

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 ~4520KB of hex-encoded data inside \objdata sections — may hide a payload
  • OLE object data medium RTF_OBJDATA
    RTF contains 2 \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_off000000b2.bin
af3ea5a2a5c5172e7816d783fbf106dfee53f09120683b8d5b40bda8db7aa542
rtf-objdata-decoded RTF \objdata at offset 0xB2 2260222 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.