RTF malware analysis — malicious · b5a35d3ae1dee365

MALICIOUS

RTF

283.6 KB Authoring application: Riched20 6.3.9600 First seen: 2021-06-17

MD5: a7460a84c7c8a523d870cf80299a64d5 SHA-1: a23974fef8bc40cc54e4999c975b7ae73576f4f0 SHA-256: b5a35d3ae1dee365ef6f58717570c678ca07ca92c7158afc85788dd24ed5bcc3

240 Risk Score

Malware Insights

MITRE ATT&CK

T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF file contains an embedded OLE object specifically identified as an Equation Editor object, triggering critical heuristics related to Equation Editor exploitation. This strongly suggests the file is designed to exploit CVE-2018-0802, a known vulnerability in Microsoft Equation Editor, to achieve arbitrary code execution. The ClamAV detection further confirms its malicious nature as Rtf.Exploit.CVE_2018_0802-6624871-1.

Heuristics 6

ClamAV: Rtf.Exploit.CVE_2018_0802-6624871-1 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Rtf.Exploit.CVE_2018_0802-6624871-1
Equation Editor object class critical RTF_OBJCLASS_EQUATION

Object class 'equation.3' references Equation Editor
Equation Editor ProgID + OLE object high RTF_EQUATION_EDITOR

RTF references Equation.3 ProgID alongside \objdata — likely Equation Editor (CVE-2017-11882 / CVE-2018-0802 / CVE-2018-0798) but without the binary CLSID payload, so flagged at HIGH instead of CRITICAL.
\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.

Filename	Kind	Source	Size
`objdata_00_off00000100.bin`	rtf-objdata-decoded	RTF \objdata at offset 0x100	16968 bytes
SHA-256: `56b207d1a3bf7344344fb8c96d44b017041299e183d1d98b3eb6bfdb183998b0`

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