Malicious PDF — malware analysis report

Static analysis result for SHA-256 421fb3220344b818…

MALICIOUS

PDF

75.0 KB Created: 2021-09-02 13:46:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 377184c6a8aaa6b87ac3cbfc0be467d2 SHA-1: 35aa5fbdd458ff4cfc0324a54a1c586900016920 SHA-256: 421fb3220344b818bfcec1ab1b2229568455bf671ff3533f82886f88889447e1
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to numerous external URLs, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were directly extracted, the PDF structure and URL analysis suggest it's designed to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://africanresearchcenter.com/userfiles/file/jilus.pdf In PDF document text
    • http://bluecars.pl/userfiles/file/54324409812.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/nelonisofisavezezum.pdfIn PDF document text
    • http://perfectionistpaintingnj.com/ckfinder/userfiles/files/52530207296.pdfIn PDF document text
    • https://dichocungtoi.com/userfiles/file/zinumulezavedotaj.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc84eae544---vorobovik.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/nefasosubotukaxufub.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/mq5jiffeetsd22hqj578epltd0/vezikojomatip.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/jazovinukuvudek.pdfIn PDF document text
    • http://wellnesszeewolde.nl/site/data/ws/files/xejumelitedewukonasi.pdfIn PDF document text
    • https://bbox.ru/images/shared/file/sokotamovudujo.pdfIn PDF document text
    • http://www.psoealora.es/ckfinder/userfiles/files/3700478893.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/4053eaa88fd1a5f2a4a5b73efe2d8779/gutekixakidabu.pdfIn PDF document text
    • https://londonvipchauffeur.co.uk/wp-content/plugins/super-forms/uploads/php/files/a0bfd5c64f5120bfb1839cb889836dcd/58839783596.pdfIn PDF document text
    • http://www.fdconsult.qa/public/uploads/cms_files/84334457269.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/p6boeprhs9g0fosri9e28kkkeg/82937856650.pdfIn PDF document text
    • https://grafconsulting.pl/Upload/file/jupoxogumowirajewojuk.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16087624232694---kababibozulizeluf.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab0b978fca9---43000463886.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/m6p51di811pm28pgrh65li9snv/93353486697.pdfIn PDF document text
    • http://sbstroy53.ru/img/files/38447646560.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160873fc19d37f---bitidezifomitimuxunu.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e33205bc76---nesadedexikesipapirefap.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/k98sp5285dpoo984ot6eqeckr0/10778318357.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=shiva+tandava+stotram+lyrics+in+english+pdfPDF 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_off0000ba02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA02 11320 bytes
SHA-256: 774cf11fdfc01587d4890b103a248ef60f2f71e580e476edeaeea9e17bbd2272
font_01_sfnt_off0000d445.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD445 18760 bytes
SHA-256: 08e3b211b77ed1b21e932d6956adf1887466761568186098ef98461579b64e37
font_02_sfnt_off000105b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1