Malicious RTF / .DOC — malware analysis report

Static analysis result for SHA-256 25c91708366c53d6…

MALICIOUS

RTF / .DOC

164.7 KB
MD5: 5e47038f8cdb1d651c514c81e3cdef00 SHA-1: 1c1d459d0f96b513f48726ce2d61dfbd0b6f4bca SHA-256: 25c91708366c53d607b7b0bec1beac89b4ee9b14a4431e5e5accda9c678ba42b
142 Risk Score

Malware Insights

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

The sample is an RTF document containing an embedded OLE object, specifically targeting the Equation Editor vulnerability (RTF_EQUATION_EDITOR). The RTF_OBJUPDATE heuristic indicates that the object is designed to be activated automatically upon opening. The extracted artifact 'objdata_00_off00001bd6.bin' is likely the payload or a component thereof. The lack of document body text or script content prevents further analysis of the specific payload's actions, but the exploit vector is clear.

Heuristics 5

  • Equation Editor CLSID critical RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • \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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object
  • 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_off00001bd6.bin
f5132469c42152e9ccc051a624691ba9d8601cc2d4db9bdc76061de62ca87023
rtf-objdata-decoded RTF \objdata at offset 0x1BD6 64575 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.91, consistent with packed or encrypted content.