Malicious PDF — malware analysis report

Static analysis result for SHA-256 665cc8c1c31c10cb…

MALICIOUS

PDF

79.2 KB Created: 2021-10-12 09:30:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 9e922a699e4b60fc084c315a421f8a0e SHA-1: 2711d906579330b34884f6b6e79c55ae46b9d1f0 SHA-256: 665cc8c1c31c10cb5a141eb32bf81568a612225bcf653af4ad1f46aa71e4da41
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code or initiating redirects. The presence of numerous external links, many pointing to compromised CMS uploads and disposable hosting, strongly indicates a phishing or malicious content distribution scheme. ClamAV detection as 'Pdf.Phishing.Trojan' further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.natursany.com/ckfinder/userfiles/files/munevobinexaledurulibasut.pdf In PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a8a98ea74c---38092689557.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/nepizefevidotefojijozegux.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/46715712980.pdfIn PDF document text
    • http://battlegrouponline.com/app/webroot/js/ckfinder/userfiles/files/34159957624.pdfIn PDF document text
    • http://tatugigo.com/ckfinder/userfiles/files/nabasesaxoduw.pdfIn PDF document text
    • https://aquamedicasatumare.ro/ckfinder/userfiles/files/nabofemalitususojotuben.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/davolilaxuxegifimetap.pdfIn PDF document text
    • http://mallenmediations.com/mallenmediations/images/userfiles/file/wojub.pdfIn PDF document text
    • https://solidpractise.com/files/userfiles/file/40094572397.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/kivibogedagisogoba.pdfIn PDF document text
    • https://metrosecuritynepal.com/assets/userfiles/files/4171861800.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/2c8ae5dfccaddea4b81627483b914fba/28873768964.pdfIn PDF document text
    • http://xn--d1achljw0b.xn--p1ai/content/upload/26013642995.pdfIn PDF document text
    • https://moraure.net/js/ckfinder/userfiles/files/fiponupibobanevajilolez.pdfIn PDF document text
    • http://worldtile.net/jangheung/userfiles/file/mozub.pdfIn PDF document text
    • https://cncunse.com/d/files/79458663977.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/zajaxe.pdfIn PDF document text
    • http://ndt-tl.ru/upload/file/10261961868.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/d132aa707c68437283abd72e9437179e/vowirasudoponejerukisi.pdfIn PDF document text
    • http://xy-interior.com/uploads/files/202110010423164490.pdfIn PDF document text
    • http://banlinhkienlaptop.com/userfiles/file/94313895511.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/RhDyTiV0TgQ/uplcv?utm_term=what+is+youcam+miragePDF 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_off0000c566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC566 10736 bytes
SHA-256: 2912d6239747aedff1837d4b7cef6b66011d00dec81f239f9dbe54bd1f0d2b19
font_01_sfnt_off0000de39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f64b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF64B 21108 bytes
SHA-256: 69d5c745ad2e00855e8593e8c833285224e77933b57a0adeb722ffe7eeb939f6