Malicious RTF — malware analysis report

Static analysis result for SHA-256 8cb5efcf03e518f9…

MALICIOUS

RTF

141.0 KB First seen: 2020-07-24
MD5: 774c85f456a9f1ce17c23acc20c76c3f SHA-1: 31d6255ab031aa1ffc5456a7c0eac142824bddac SHA-256: 8cb5efcf03e518f9097ed780b860e41f58414f4a1abb733db4915c5932ba8bbf
300 Risk Score

Malware Insights

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

The RTF file contains embedded OLE object data, specifically identified as an Equation Editor exploit targeting CVE-2017-11882. This vulnerability allows for the execution of arbitrary code, which is a critical finding. The presence of this exploit strongly suggests the document is designed to deliver a secondary payload, likely through a spearphishing attachment vector.

Heuristics 7

  • 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
  • Equation Editor Ole10Native payload — CVE-2017-11882 likely critical CVE likely CVE_2017_11882_EQUATION_OLE10NATIVE
    RTF decodes to an activated Microsoft Equation 3.0 OLE storage whose payload is a high-entropy Ole10Native stream rather than normal Equation Native/MTEF data. This is a weaponized Equation Editor RCE delivery shape consistent with CVE-2017-11882/CVE-2018-0802.
  • 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
  • Embedded OLE object medium RTF_OBJEMB
    RTF contains \objemb — embedded OLE object

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objdata_00_off0000003b.bin rtf-objdata-decoded RTF \objdata at offset 0x3B 45604 bytes
SHA-256: 8a144e1f98aa31dec3ef4e4f614f7fdf53173b1eab8fa0188bb5a91ce07c0038

Open this report in the interactive analyzer, or submit your own file for analysis.