Malicious RTF — malware analysis report

Static analysis result for SHA-256 8c933a2975488091…

MALICIOUS

RTF

9.1 KB First seen: 2018-05-18
MD5: b025e643d5d5446190268a3ee4d1ce4e SHA-1: 6569d19cf87c11b2d7900827e3603edccd8e473f SHA-256: 8c933a2975488091afcfb1cc1c783d1ff9029cbadbb9a7ef0c67a61e553b3f12
240 Risk Score

Malware Insights

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

The RTF file contains embedded OLE object data and triggers heuristics related to Equation Editor exploits, specifically CVE-2017-11882. This indicates the file is designed to exploit this vulnerability for client-side execution. The ClamAV detection name further confirms this exploit. No specific malware family could be identified.

Heuristics 6

  • Equation Editor CLSID critical CVE likely RTF_EQUATION_EDITOR
    Equation Editor OLE CLSID found inside an OLE object — exploited by CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798
  • Ole10Native stream in RTF OLE object high CVE related RTF_OLE10NATIVE_STREAM
    RTF contains an embedded OLE object with an Ole10Native stream. This is a strong payload-container signal and is related to Word/OLE exploit delivery, but it is not specific enough on its own to assign a CVE.
  • ClamAV: Rtf.Exploit.CVE_2017_11882-6584355-1 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Rtf.Exploit.CVE_2017_11882-6584355-1
  • \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 medium 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_off0000003b.bin rtf-objdata-decoded RTF \objdata at offset 0x3B 4645 bytes
SHA-256: 8fdcd84dc3a6445772c4e7ff76b7a4029cf7871697c77bedb77df66e3f0a997e
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Static shellcode analysis found candidate code region(s). Indicators: SC_GETPC_CALL