Malicious PDF — malware analysis report

Static analysis result for SHA-256 673cf1e1d8c6547a…

MALICIOUS

PDF

87.8 KB Created: 2021-09-02 20:33:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 10fbe20daaf13a2b3a66b0d831c9b9d3 SHA-1: 8fc01607c5e37eb7b193614605bf5e123b94898b SHA-256: 673cf1e1d8c6547a78314e0d2e5f2b894d26be2d150594fb8768ef48a1bc3ec0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to domains associated with compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://alphanaturehk.com/userfiles/file/bukesaziwinovinefi.pdf In PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160de0c7979ba6---fuxijoxubibuxop.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608195815918f---kibunigo.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/fa553a5a295b9ab7b79c35c42be69605/35409684131.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba51018ca86---34577199157.pdfIn PDF document text
    • https://mgc.to/sites/web/upload/files/bopixogigewiruluge.pdfIn PDF document text
    • http://digifast.cz/userfiles/19073675804.pdfIn PDF document text
    • https://goodnest.info/tctt/sites/aaa/file/41509527451.pdfIn PDF document text
    • http://interel-rus.ru/test/sites/default/files/file/59638203010.pdfIn PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/a90f70e7d5389e7d21461343a055aed2/vizolikodavotu.pdfIn PDF document text
    • http://cathugo.de/res/wysiwyg/file/dodim.pdfIn PDF document text
    • http://billsky.ee/files/file/73421270712.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086c7220268f---gikuwurusidowula.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a447c65f9b6---kukusoxuzizuzajigiliziv.pdfIn PDF document text
    • http://xn--9n2bn9mz3aba29g44r4o0a.kr/fckeditor/userfiles/image/9851805517.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/savibomugudejoxepuzog.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/17140038650.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160848da05dad3---87234072734.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/xinusejumilu.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/76972952817.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073a583b5c06---kazuburigapexam.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/87076829007.pdfIn PDF document text
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/8de06c15a7081cfb3197a5cc62aade3d/vixepipimopabodulibo.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c976106d830---lozolajadujekijo.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/rget8nmmthcl8fal3clgm2pd14/61894629022.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=strategic+sourcing+case+study+pdfPDF 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_off0000f07c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF07C 18004 bytes
SHA-256: c77a88d4fa2c8c57c2e5be20e6bd700e34984502fcc40963291774beef28f5f1
font_01_sfnt_off00011f44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F44 11040 bytes
SHA-256: bc7fe6f80b240ce0a9c65c86b2596f92186a31d28e396241ae6307185fe02025
font_02_sfnt_off000138e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1