Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb8d7b82de84e870…

MALICIOUS

PDF

80.0 KB Created: 2021-03-24 04:28:30 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 33cf5b6aa303a6d4fa17d22f9a8d7194 SHA-1: 76faf698087dad4e5932a54f933e6ea47503fef9 SHA-256: cb8d7b82de84e870c3d3d7c05acfc13faa843a063786966527e29d77b7671b8a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains heuristics indicating an external URI and is flagged by a machine learning classifier and ClamAV as malicious. The embedded URL, 'https://dafemum.ru/strik?utm_term=walmart+black+friday+november+25+2020+ad', is likely used to redirect the user to a phishing or malware distribution site, disguised as a Walmart advertisement. No scripts were extracted, but the PDF structure and external URI suggest a phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://dafemum.ru/strik?utm_term=walmart+black+friday+november+25+2020+ad
    • https://cdn-cms.f-static.net/uploads/4372073/normal_5fd2f5836ab1d.pdf
    • https://cdn-cms.f-static.net/uploads/4484834/normal_60421c5d26887.pdf
    • https://cdn-cms.f-static.net/uploads/4413120/normal_60371302aab87.pdf
    • https://cdn-cms.f-static.net/uploads/4489844/normal_60164db6322bc.pdf
    • https://cdn-cms.f-static.net/uploads/4425728/normal_602d7abb63c60.pdf
    • https://static.s123-cdn-static.com/uploads/4392193/normal_5feb5cc533a09.pdf
    • https://cdn-cms.f-static.net/uploads/4426810/normal_6044d3b58659c.pdf
    • https://static.s123-cdn-static.com/uploads/4478927/normal_5ff5bac3376a1.pdf
    • https://cdn-cms.f-static.net/uploads/4464865/normal_601a62b2be926.pdf
    • https://cdn-cms.f-static.net/uploads/4461481/normal_600a3c522ed2f.pdf
    • http://bixekakazozerol.mywebcommunity.org/7370995704.pdf
    • http://bexowobiminefi.mywebcommunity.org/forcepoint_category_list.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/0f1c3e52-ea59-4a29-9c8c-65b6a5360081/define_base_rate_neglect_in_economics.pdf
    • https://uploads.strikinglycdn.com/files/b1df29cb-f6d9-4734-9240-2dfb8f58ccaa/16861411815.pdf
    • https://uploads.strikinglycdn.com/files/529d3f4b-0d7d-42df-a2d7-ef06ac4be697/tirosiwigipoburomitez.pdf
    • https://uploads.strikinglycdn.com/files/768d5939-4b9e-4693-ab88-81529aa293cf/8147596167.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7d2.bin
9f61db9b0c8ed6f0f27d087668a525d666969ce27d340c915e1c161650b8c5ea
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D2 5768 bytes
font_01_sfnt_off00010b83.bin
8f56e464dcb4600e5b10dc80f71384e11b33b0e016d6df32f7394e4eda0195b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B83 11696 bytes