Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc81f122240c38b9…

MALICIOUS

PDF

114.8 KB Created: 2021-06-23 20:37:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 5a1eda438b765144d308ce57bbdfc733 SHA-1: d0b66eb352db81fd9867cd3d8a37f88cb4849ef5 SHA-256: bc81f122240c38b91734ec8bdc7b0e8ca835c2b831b5fcc12ed41adf243b7c29
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://teenmag.cz/userfiles/file/13268101427.pdf In PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609da47b3c3e8---32284580832.pdfIn PDF document text
    • http://photo-preiss.com/upload_files/files/89930596351.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/xewesupuzanig.pdfIn PDF document text
    • http://ciccioinpentola.com/userfiles/files/losasovidigomoxodo.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b1301dc3162---rerixeviwosedopaxoladob.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/gq0s8oj05sddi033rhqkmrvks7/sekonoror.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160c84c6742202---40727004431.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b4760db3f1b---80496846188.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/ab957733372762f8f0bff2ae013f18be/pejusa.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/ec25c9e690740f4f7183607b227e96a3/9807592668.pdfIn PDF document text
    • http://tai-group.com/upload/files/36055293788.pdfIn PDF document text
    • http://lhs75aa.org/clients/0/08/08eb77d093c5251d787cf05842b4a73c/File/2885380560.pdfIn PDF document text
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/peg7jc65aj7bhi2apkkn2k2td5/nelanozipujo.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/0e70253d175097ed5b23e4783dd9fbc0/26903062784.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088e83077239---35237942904.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=google+matrix+pagerankPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000184e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x184E7 5124 bytes
SHA-256: db69c8bebeb1fbf8666dbd8e80ccd78d5131e4a92eb7944956cd7a240c76ab3b
font_01_sfnt_off00019648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19648 11936 bytes
SHA-256: e6b4b48b8231ef64628f3e76bd8ca44636557e66a195bc9dc9847adf49201404