Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 6810cc6edb1ced93…

MALICIOUS

RTF / .DOC

129.5 KB
MD5: abb6916bdf5c4028fa49c614c200f180 SHA-1: 79017f043d266043ce042fa654c89b8af9c163f4 SHA-256: 6810cc6edb1ced93f416b478d0d793b3a01bcfd37d8927388fd55ec2b1086e29
122 Risk Score

Malware Insights

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

The RTF file contains an embedded OLE object that is related to CVE-2017-11882, a known vulnerability in Microsoft Equation Editor. This vulnerability allows for arbitrary code execution when the object is activated. The presence of \objupdate further indicates an attempt to trigger this activation. The file is classified as malicious due to this exploit.

Heuristics 4

  • 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.
  • \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_off00000044.bin
3a4cccf2acf895b56bb348df9deed94ca7b2d1b52a6df27bf75cb3dedc8c6c83
rtf-objdata-decoded RTF \objdata at offset 0x44 66185 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 8.00, consistent with packed or encrypted content.