Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3caa52d4ff466df…

MALICIOUS

PDF

74.7 KB Created: 2021-08-27 18:50:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: eb0d108b05c7e4fba5c637d4b94a0bef SHA-1: 0d2e7b5cf2df6b1b91faa14c43e2929c9bc89e9e SHA-256: b3caa52d4ff466df632988f7a64f78b367909286fa9394de4d0ad22d56a2680f
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it as malicious. It contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The PDF structure and link farm indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a26a33a0ef2---17304261579.pdf In PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ac09a6b8e40---xomaroboliv.pdfIn PDF document text
    • https://grnca.org/img/files/files/kebunubebibejogebufovomuf.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/rumitixubafadapirutalake.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/31045112066.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/56263856.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/emsgkgelakett8cvahif0epj86/43499435729.pdfIn PDF document text
    • http://henrycrawfordreunion.com/clients/1/19/1929e20d1ffebcad6d8b2a659e9c170d/File/73258549294.pdfIn PDF document text
    • http://gandolfiarchitetti.com/userfiles/files/40040275688.pdfIn PDF document text
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/02qvo4ci0m35ndg3cpg5fqsgo3/70434411414.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/520ae8ca76cb8ba1ba08c0208dc052c9/muzudogosafowato.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/lta54fc828q65q212hjt26iteu/84737028333.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/a7e4ad871eeecd1b91d448d1006e780f/91708292849.pdfIn PDF document text
    • http://orsini-blasioli.it/userfiles/files/66408259643.pdfIn PDF document text
    • https://actor-conseil.com/files/file/lotipabuv.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210628080930.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9878a6688b---zuretodima.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160990bb2bb8b2---52191449311.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090d5eb02f79---segikadi.pdfIn PDF document text
    • http://www.agot.pl/upload/file/24152715544.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160768fb780fcb---burokizagekibitumis.pdfIn PDF document text
    • https://mkycc4.com/kycc4.com/userfiles/files/48529556443.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/67292155267.pdfIn PDF document text
    • http://minerva-collection.net/files/files/20695379311.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=another+word+for+ostensiblePDF 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_off0000c181.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC181 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD993 16972 bytes
SHA-256: deae506357e35c0bf2b758ab5aaccf969a9dc8ffcb86b4221bfda68bc68568b9
font_02_sfnt_off00010596.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10596 10496 bytes
SHA-256: 1610df1060d31919fc66d2435093259267d394159ad9c125eeb2127c7fa4b9ac