Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b20f3a72a47865a…

MALICIOUS

PDF

77.2 KB Created: 2021-03-08 19:50:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 88beb0155f382078e22e1dbc54b62e75 SHA-1: 1a8ba0ecc340625cd6703a06a342922ed6e63c9f SHA-256: 3b20f3a72a47865aac0e15b8d3ee0facc0eea2b9797c234cf7c264e76a4914ac
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable domains, indicative of a link farm. ClamAV and ML classifiers identified this as malicious, specifically a phishing trojan. The primary function appears to be directing users to potentially harmful content through a network of linked PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://jumiwimov.ru/award?keyword=canales+de+comercializacion+pdf PDF link annotation
    • http://info-pages.ru/headache_diary_printablea5f0r.pdfIn PDF document text
    • https://viwosexoteb.weebly.com/uploads/1/3/4/6/134631328/tuxazanaru_zenimi.pdfIn PDF document text
    • https://zasuzepomuban.weebly.com/uploads/1/3/4/6/134627511/b8269fed3f4.pdfIn PDF document text
    • https://dirasikazeta.weebly.com/uploads/1/3/1/3/131379856/sibunabo.pdfIn PDF document text
    • http://aicberg.net/scag_cheetah_61_parts_diagram3jiyc.pdfIn PDF document text
    • https://mixowobigasobu.weebly.com/uploads/1/3/1/1/131164278/535983.pdfIn PDF document text
    • https://fofomakizu.weebly.com/uploads/1/3/0/7/130775640/lexatumuzipamiwugi.pdfIn PDF document text
    • http://svoylend.xyz/book_of_enoch_giants_heightdu6dx.pdfIn PDF document text
    • http://timogefubor.22web.org/chiari_iv_malformation_mri.pdfIn PDF document text
    • http://insuranceautousa.com/how_to_refill_a_dymo_letratagl6brd.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/b57561e2-1372-486a-a157-fb048ea011bf/wrist_blood_pressure_monitor_not_accurate.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c9df93f-b8f5-4095-9907-a091238deb20/frigidaire_dehumidifier_fad704dwd_ec_code.pdfIn PDF document text
    • http://zufakugofozufi.epizy.com/android_navigation_architecture_component_gradle.pdfIn PDF document text
    • https://3d7304b5-8527-495f-b913-615d6f357a43.filesusr.com/ugd/ef7486_0907fcac6673438cbdb5acf68c96d515.pdf?index=trueIn PDF document text
    • https://11f44e1d-c86f-4be6-baa1-90970e7c24f5.filesusr.com/ugd/a298ce_a92fba046699460490d01b90eb5842ef.pdf?index=trueIn PDF document text
    • https://8d90b851-447f-4cfc-ac95-1e867b71b983.filesusr.com/ugd/b371d9_ac7346122d2247558250741a675b07f8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/19974304-4022-4846-9292-d192eb40d490/lonemezopemabe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e963471d-db67-4592-8597-d3e5d3dfda0b/mijifono.pdfIn PDF document text
    • https://d04c2b29-3777-4fe6-aaa9-ab96f87c3324.filesusr.com/ugd/43eb95_d2fd6649d2764de6b024da90880a0d68.pdf?index=trueIn PDF document text
    • https://fd01a0c1-3a12-4c3a-bf6b-9bb85f9b1b15.filesusr.com/ugd/f9d4cd_f189ac69de654842afd9f8551c60880a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c0f02368-e578-4654-85f0-531a8f0dee0b/38924639334.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c57b5f8-2215-44a1-be55-74a7272f5865/nitepidojusesefe.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE49 5256 bytes
SHA-256: dcb4c642f8994f0613756bc80e8b0b47367aa46eb7a7f1e3ae3115a7738843ea
font_01_sfnt_off00010017.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10017 11632 bytes
SHA-256: 3862092c5486bea6ec42c3dda3c96cd85f5a38027d05511fed514ec467e9ca17