Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f0b90f93a0d06bb…

MALICIOUS

PDF

115.8 KB Created: 2021-07-06 12:09:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0b1ea3082af9a73ae8c5e3ce89f42efe SHA-1: 975793d96f6eaf022a5ce610f1b3fc5e21538825 SHA-256: 4f0b90f93a0d06bbb08b573d18420d929887e76b03d0f42e76d087987fc59f6c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO abuse. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/0pjvr64du9m6uln8sl7kd16l91/7252635634.pdf In PDF document text
    • http://travelsi.ru/ckfinder/userfiles/files/xukonuvupizojepolibexotat.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/eebd8c6371b4a05263448b8ce15e9779/62143880150.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090e1e65f7da---fepazepatijexuluzatizu.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/160939fd7bbba6---lozikazixa.pdfIn PDF document text
    • https://nada70.org/userfiles/file/28548264029.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c46294b6b5c---71421921370.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa7969bce4---nulovisezegibajija.pdfIn PDF document text
    • http://phamtrangia.com/upload/files/26020100403.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/18fc004a6f6c1bcf3c0c0f280187705e/komaxotelefawi.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160854b8609f01---21346522564.pdfIn PDF document text
    • http://alarmy-kamery24.pl/userfiles/file/wudemen.pdfIn PDF document text
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/19gn1tpg3vb83gemoatfouodg5/94016662371.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/92365717313.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1ccd1e7e6---xerakapajuwexapeluxidexu.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/ea497ce9b03e6324f25f2d81121dd3a2/rogabofi.pdfIn PDF document text
    • http://aklond.com/UploadFilesfile///2021051009112496.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5679cb83a---bisasizipag.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/5ml2l3ipnbb5c6hgigoq04lvj7/jamiligojare.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/64319906103.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160beffc925048---jegola.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c784d0e02aa---72799640010.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a51804e3db5---97477060592.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/40874481275.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=glycolysis+cycle+in+biochemistryPDF link annotation
    • 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_off00015f3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00017754.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17754 10628 bytes
SHA-256: 9e0bc2e4746c8a2b129ec94e7c362198ff5d1cc22c33f15e605091258aec1ece
font_02_sfnt_off00018f72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18F72 19068 bytes
SHA-256: da1891df4fb8d39793b129651e5a65b010a6af0b6a033bc5908ccfaa2079d9ef