Malicious PDF — malware analysis report

Static analysis result for SHA-256 a04c4f3318e601c8…

MALICIOUS

PDF

80.0 KB Created: 2021-09-23 01:07:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 88baec008ef9eb69ab4a57c3a6f0b1b7 SHA-1: 53080cb4320d2acd932dbc8f0e9343b85551ed7c SHA-256: a04c4f3318e601c8c7ecb24a4524e7b565fd08dfb9f6cd0cdb7d57c5a75ff3a6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous external URIs and links to potentially compromised CMS upload storage, suggesting it's designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://irlanc.ru/uplcv?utm_term=send+message+to+firestick PDF link annotation
    • https://butzbacher.turnpoint.jo/app/webroot/upload/files/kefuxarilopotixuguwef.pdfIn PDF document text
    • http://datacomsystems.cz/userfiles/file/niximaverejijirupe.pdfIn PDF document text
    • http://laguna.piyawatgroup.com/images/files/14416352953.pdfIn PDF document text
    • http://sgrdpandher.com/userfiles/file/20131222443.pdfIn PDF document text
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/sokorezebajebuzizejaga.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/0cec0619515aef6e5324749819dd05a1/52389673284.pdfIn PDF document text
    • http://xlith.com/userfiles/files/22173104561.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202109080910364867.pdfIn PDF document text
    • https://gppacdatabase.net/userfiles/file/43887653285.pdfIn PDF document text
    • https://flomogroup.com/upload/files/88062952398.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/95389428206.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ce5665d8c---wikasivonipomedumewixoji.pdfIn PDF document text
    • http://iranjobex.com/cache/fck_files/file/folurewefabo.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/161336cb4dca5e---78654730622.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/fofeduwex.pdfIn PDF document text
    • http://sd-admin.fazendapenaazul.com/ckeditor/uploads/files/ratute.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614aece9e8cce---69172739482.pdfIn PDF document text
    • https://doxity.ro/ckfinder/userfiles/files/xumesegipilesivojopofo.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff8375caa1---28877998141.pdfIn PDF document text
    • http://lightningriskassessment.com/ci/userfiles/files/tisowewefusefu.pdfIn PDF document text
    • http://mamnonhieutrung.edu.vn/ckfinder/userfiles/files/fibaduleluwusanidedam.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_off0000d3c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3C6 17480 bytes
SHA-256: 132cd3d289567cc73b86269708a71be36bd7f9faa4ecdf77b60d7e3b2c28fa8d
font_01_sfnt_off00010182.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10182 10940 bytes
SHA-256: 641d73f2649b61f07da20dbc878caa2a4419e76d7de0bbf76688e5b6e30e34df
font_02_sfnt_off00011aad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1