Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee658ad8b2516fae…

MALICIOUS

PDF

95.1 KB Created: 2021-09-02 04:46:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 85e7bde469f293d7ed7ae9d461786ac5 SHA-1: 25edec9d4fab73d0321346bf8143841343cf053c SHA-256: ee658ad8b2516fae05a12647a9c69722b0f7485b1b0809b52cc84df23933f1f7
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress upload directories and other disposable hosting, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://krisoc.ru/uplcv?utm_term=canon+powershot+sd870is+manual PDF link annotation
    • https://apskarota.org/userfiles/file/kizegaxuneso.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/vr46q9bc2uqe00qulhls5v5075/95390001550.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/qk9amr1rt6m079tui06n5o1d7c/86944227552.pdfIn PDF document text
    • http://maytinhtuyenquang.com/home/maytinhtuy/domains/maytinhtuyenquang.com/public_html/images/file/30786802952.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/lanofi.pdfIn PDF document text
    • http://investin-khj.ir/ckfinder/userfiles/files/1571610856.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/jijikolatujomagoped.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/a837a434f3a65b0fc0806eb9d8124974/rujuxamutesirejeduki.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bc4798ee99---wunejazalalitexiwad.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/gobivuluzaxew.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc65e88be0---66678099737.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c13210d26da---pawumes.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/c20700aee0770e5c976905d9f09f5013/99330484694.pdfIn PDF document text
    • http://wwstationery.com/files/file/lopupaliwibuzajojegemasoj.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/37533779854.pdfIn PDF document text
    • http://cgl.lu/userfiles/files/35103032451.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b30d72ede40---porixisitoximad.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/aad2770c2ed7a6c440c4bc32db86178d/9970580177.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/femeti.pdfIn PDF document text
    • http://artgraf24.pl/userfiles/file/kepifovamejaxizadosupudak.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/1spuoqn0rc5jv3mi7q1d5agoap/3766858780.pdfIn PDF document text
    • http://shepardfarm.com/clients/877021/File/wixizewimosikojibedumof.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16084cbcd1c86e---2043535034.pdfIn PDF document text
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/da7e00fc8b0a66de9ccc6d22a2e619a1/vebojugakof.pdfIn PDF document text
    • https://thietkewebseo.com/webroot/img/files/7521888582.pdfIn PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/porag.pdfIn PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/ruveremifiw.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010acb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ACB 11252 bytes
SHA-256: 79745f298b25e1fd37162dbce3aeb64c5b6fed178246cc18312422183e271493
font_01_sfnt_off0001251b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1251B 18692 bytes
SHA-256: 10b3d91195012aed1c2300b8ba65e556c63fdafa74acb939a00fa55be1bfb7dd
font_02_sfnt_off000155f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x155F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1