Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef3b352d47b68935…

MALICIOUS

PDF

77.4 KB Created: 2021-06-21 18:14:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 7f914aaab45e9a1eedeb4187b7d15288 SHA-1: eab50c73bfdaead3402c91dab790dde6da4d19d5 SHA-256: ef3b352d47b68935a4415929221a2674170f642750a24ad7c1edded01a516d0f
96 Risk Score

Malware Insights

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

The ML classifier strongly indicates maliciousness, and the PDF contains a link farm pointing to compromised WordPress sites, suggesting an attempt to distribute further malicious content. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and 'Qt', indicating it was generated by a tool rather than being a legitimate document. The presence of numerous embedded URLs, many hosted on potentially compromised or disposable domains, reinforces the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/7cc85475dd139b47839f6b68620bc3c2/rujumaxidudamaxukazajego.pdf In PDF document text
    • http://aarogyamedico.com/userfiles/file/vosukubujurarusizudori.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/tidejuxufipi.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/986982eb4fe0c0bd364a22e07215920e/darolukopafigozaziwilezi.pdfIn PDF document text
    • http://9meclinic.com/ckfinder/userfiles/files/65616494239.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608604ca0cf0c---59089832938.pdfIn PDF document text
    • http://zulassung4you.de/bilder/file/bovamateleramafenaloj.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/fc57a1e80529f13a6a70ed34a702e38a/lisopetepanutovalijuj.pdfIn PDF document text
    • https://ises.ca/phpsites/vertical_living/uploads/file/dozokanaromojapitujo.pdfIn PDF document text
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/1e9e44ff526efa25a9bfe5d206547fb6/50873560832.pdfIn PDF document text
    • http://debeleven.net/UserFiles/File/50089202864.pdfIn PDF document text
    • https://bladmedyczny24.pl/wp-content/plugins/super-forms/uploads/php/files/5568084114cff94862fde384a4ca6583/50709316311.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/2d576cc1273e3379e91521a90b453df0/nobukugazoleg.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/18222380343.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608acbfe5046f---lebazufozovafetanumixoke.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6baee457c---61442780994.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c78c5ac88b---26231344199.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/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+fix+a+broken+guitar+string+electricPDF 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_off0000efb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB8 5372 bytes
SHA-256: 8eb016b90347d8724f6ed08a39e690a9cb5263ce3fad84516b241d781263eec2
font_01_sfnt_off0001022e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022E 10592 bytes
SHA-256: 863d854f95c879f299fd4af4501ee4b59d102081ad9ace1c758b51373c1007f6