Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6f2addfd03b3e6bf…

MALICIOUS

RTF / .DOC

349.0 KB
MD5: 9d9e52016d0cde337c41262d0022cc4c SHA-1: 0f34fac46fd81df6e0819f98baae6b471e0499ae SHA-256: 6f2addfd03b3e6bf0f387c0a30b3921c0ff4ce59bb77d24bfdbbeaf68f35a14d
222 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 exploits the CVE-2017-11882 vulnerability in Microsoft Equation Editor. This vulnerability allows for the execution of arbitrary code, which is likely used to download and run a secondary malicious payload. The presence of the Equation Editor OLE object and the associated heuristic firings strongly indicate this attack vector.

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_off0000129e.bin
ff76c37c668dca93b5d0807a3ce82106eedcbff45c29643b1a2c432ac2a674ef
rtf-objdata-decoded RTF \objdata at offset 0x129E 100380 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.