Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 03c7a60ce4c7c66a…

MALICIOUS

RTF / .DOC

830.9 KB
MD5: eda690a74ead90fff4d105468d67fdf1 SHA-1: aa9c89b046bd9a953f3aac1a79ca6bf89ee4f48c SHA-256: 03c7a60ce4c7c66a2cc10f67a908804f8705b872eb95f57bba6d004b1380acf6
182 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object, specifically related to Equation Editor (CVE-2017-11882). The heuristic firings indicate the exploitation of this vulnerability to execute arbitrary code. The embedded object's native payload has high entropy, suggesting it is likely a packed or encrypted second-stage payload.

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.
  • 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.
  • 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_off00000043.bin
096da4b25f946d26caa4f38c95b4fcd6368969ec55a4eaf3650a90a60e66cdef
rtf-objdata-decoded RTF \objdata at offset 0x43 425271 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.