Malicious RTF — malware analysis report

Static analysis result for SHA-256 7fcaa10eaad97563…

MALICIOUS

RTF

14.3 KB First seen: 2019-03-10
MD5: 2d6102c6321861679b10cf35e8519a8d SHA-1: 860f324764d6f192291e0f7b101616c69d76664e SHA-256: 7fcaa10eaad975639612281dcd746b3d4e5f4d38bf8b14c5a92cdab4b1e3c447
220 Risk Score

Malware Insights

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

The RTF file contains critical heuristics indicating the exploitation of CVE-2017-11882 via Microsoft Equation Editor. The presence of OLE object data and the \objupdate directive further support the execution of embedded malicious content. This exploit is commonly used to deliver secondary payloads, hence the high confidence in an attack pattern involving code execution and potential payload download.

Heuristics 5

  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off000014bc.bin rtf-objdata-decoded RTF \objdata at offset 0x14BC 4649 bytes
SHA-256: a6718b1551c379d51e227f237c736d4793372ab0b1e9bc4b0938844463bbb6e7