Malicious PDF — malware analysis report

Static analysis result for SHA-256 31f46f4e60c2de13…

MALICIOUS

PDF

83.6 KB Created: 2021-08-20 15:50:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 18fba6ef615904bb7b08767eaff3605b SHA-1: 1d597f49b7b84e725dd61ecda1a36f7cf0c7b0ca SHA-256: 31f46f4e60c2de13aa0b9a93b7260e1951f5c4aedbb2399d2f0b943858adaa26
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm heuristic suggest it's designed to redirect users to malicious content, potentially leveraging embedded JavaScript for obfuscation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://sealskinz.ru/files/file/83787417604.pdf In PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/54501482099.pdfIn PDF document text
    • http://buddhavehicle.com/userfiles/file/8573042451.pdfIn PDF document text
    • https://hansenlight.com/UploadFile/files/36760003866.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160847f1cc9d23---jasibujawivuvebubolumos.pdfIn PDF document text
    • https://exihomes.com/userfiles/files/38784820741.pdfIn PDF document text
    • https://dalyanestate.com/userfiles/file/wuletebalolomopodugenagu.pdfIn PDF document text
    • http://mamitobe.ru/files/file/luforajebemapusikinuzur.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/pgjtueis3vrf7f131ok51ekgk1/sovezevujoxovufonut.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/renumalipuwukixu.pdfIn PDF document text
    • http://mopron.ru/upload/files/97711515716.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/1c8908c6c406692579b84d3b2fd01cc4/lotimilo.pdfIn PDF document text
    • http://bjjiffy.com/upload/xobudavafinisodesotemi.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/e31bf875d89ae99be50c57a284298a97/7662649541.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16090f4c25005e---8419327027.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16071a4b88edc0---27885307267.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/biifr3mig3d5o23qt8l23qcc3p/dowewef.pdfIn PDF document text
    • https://ksi-system.pl/editorfiles/file/sixazubanukezasozusirose.pdfIn PDF document text
    • https://swalaya.in/userfiles/file/zemilomularamozokikaz.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb5aa61e751---gixaforowovojugukozodi.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/f6f22bc2c863f38c11d041ed15a2515b/zosegabivejipozixorope.pdfIn PDF document text
    • http://paolacaone.eu/userfiles/files/wimofugadifofewos.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a962ae60d85---bezazubojetax.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/43c1cfe09823792fe71630e318ea998b/bozaxowitugemum.pdfIn PDF document text
    • http://concilianavarra.com/userfiles/files/22135765630.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=human+anatomy+and+physiology+marieb+10th+editionPDF 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_off0000e000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE000 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f812.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF812 16896 bytes
SHA-256: b438d343fa8fe58cf25d9b46474601597811ac591c42ec4f4bf2c0a6203e06ad
font_02_sfnt_off0001241d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1241D 11360 bytes
SHA-256: b4bb371cccf1fc02809a4555ba85f571772dc119a184c53827ab255f4d068b63