RTF malware analysis — malicious · 8d432e02804d66fc

MALICIOUS

RTF

1.25 MB First seen: 2023-01-27

MD5: 2f81e42c5b7f2bc855b23d83b7ea60f1 SHA-1: e87fc545e4c0c56de39d9c410917544d1603b5cd SHA-256: 8d432e02804d66fc9c6db1b5d79636f5caf1de4b5d4edbd154f093dd25569bd9

262 Risk Score

Malware Insights

MITRE ATT&CK

T1566.001 Spearphishing Attachment T1204.002 Malicious File

The RTF document contains an OLE object that exploits the Equation Editor vulnerability (CVE-2017-11882). This vulnerability allows for the execution of arbitrary code, which is used here to deliver a secondary payload. The presence of a decoded PE file within the OLE object confirms the malicious intent.

Heuristics 7

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.
Decoded Equation Editor payload + PE critical 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.
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.
Large hex data blocks in OLE object high RTF_EXCESSIVE_HEX

RTF contains ~1311KB of hex-encoded data inside \objdata sections — may hide a payload
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_off00000071.bin` `f453d788d3791cf5b237a04f2b4c1d1cba5f8c03efbc57fe6e63e1c30307b6dd`	rtf-objdata-decoded	RTF \objdata at offset 0x71	656133 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact entropy is 8.00, consistent with packed or encrypted content.

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