Malicious PDF — malware analysis report

Static analysis result for SHA-256 131980fb54f83964…

MALICIOUS

PDF

60.9 KB Created: 2021-06-18 12:27:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 5757e7b9af5d50784d68adedda4b9432 SHA-1: b2e31eec1dc740f4be14a1ccaa67833b6e0498d2 SHA-256: 131980fb54f839642d00a4ad5425a9631ba4bc6e4d976485e880cc7ee5bda8f1
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload directories and disposable hosting, suggesting it's part of a link farm designed to distribute malicious content or phish users. The document body, though heavily obfuscated, contains references to 'All in one calculator pro' and 'wkhtmltopdf', potentially serving as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://crysiq.ru/uplcv?utm_term=all+in+one+calculator+pro PDF link annotation
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806127ae1ed---79941947345.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160864eb3b1204---xezakalixijuge.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/3b3eb0065b06f29e05fb8ec1ce07ccc8/zobudugiwulufisusame.pdfIn PDF document text
    • https://plasy.com/uploads/file/nowusapas.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/2cdqjp5qftro8182lcf5punil5/sexivopa.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/meu908u90rb3jd0vnr4qgauksn/76561432270.pdfIn PDF document text
    • http://gabortech.com/admin/file/83049947139.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ed6e409b3---jugemakomulujujisosudib.pdfIn PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/77344595745.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/16085088a7b683---24453772222.pdfIn PDF document text
    • http://gentlemensquartersbarbershop.com/wp-content/plugins/super-forms/uploads/php/files/5d4c93e14022d13cb97ded7be99fed7a/kozovanexotakuwemajifin.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/f48v3frph15k6tqkgioha3obod/17196064366.pdfIn PDF document text
    • http://goref.ru/files/file/tomuvenodojefekogelosi.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab6438f1b09---monavasimudejol.pdfIn PDF document text
    • https://uniqrelation.com/userfiles/file/veloseluwudurabugap.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a65902746c---jijejif.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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_off0000b523.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB523 4736 bytes
SHA-256: f4d4159c050060ff23559fe081fdb945f62f4f6c76c760f3f301843d5ac9fb81
font_01_sfnt_off0000c54d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC54D 9820 bytes
SHA-256: b03f02499f096e83179b3ea1a1ccd58f7758a3cadedeecdfdc08a6be4fc7550f