RTF malware analysis — malicious · 958821639b82c77f

MALICIOUS

RTF

449.5 KB First seen: 2020-05-25

MD5: 15fb16cc291d06842d97681c18f8fe5d SHA-1: 70633a22fa4e12b8a7494eecaf0195e9ea4dfd55 SHA-256: 958821639b82c77f707f3be8d3aea4b4336ad87fb7e4bf2c4b62665a4c3497f9

222 Risk Score

Malware Insights

MITRE ATT&CK

T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The RTF file contains an embedded OLE object that leverages the CVE-2017-11882 vulnerability in Microsoft Equation Editor. This vulnerability allows for the execution of arbitrary code, indicating the file's purpose is to deliver a malicious payload. The high entropy of the decoded object further supports the presence of an executable artifact.

Heuristics 6

Decoded Equation Editor payload + PE critical CVE likely RTF_EQUATION_EDITOR

RTF decodes to an Equation Editor ProgID adjacent to OLE activation and the same decoded object stream contains embedded PE bytes. This matches the Equation Editor exploit surface used by CVE-2017-11882 / CVE-2018-0802 documents, while requiring payload evidence to avoid flagging benign Equation references.
Equation Editor OLE1 native payload — CVE-2017-11882 related critical CVE related CVE_2017_11882_RELATED

RTF decodes to an OLE1 Equation.3 embedded object whose native data is large and payload-like, and \objupdate requests automatic activation. This is the delivery shape used by Equation Editor RCE documents such as CVE-2017-11882/CVE-2018-0802, but the malformed MTEF record needed for exact attribution was not recovered.
Automatically linked OLE object high RTF_OBJAUTLINK

RTF contains \objautlink — an automatically linked OLE object surface that can be updated or activated when Word opens the document.
\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 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.

Filename	Kind	Source	Size
`objdata_00_off00000070.bin`	rtf-objdata-decoded	RTF \objdata at offset 0x70	230061 bytes
SHA-256: `d1f6185b7d15ac0cf8e7ed7b8715e11cc9327defa3f293b1b1bf0b9d2e579ea6`
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact entropy is 7.99, consistent with packed or encrypted content.

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