Malicious PDF — malware analysis report

Static analysis result for SHA-256 919b6e250eeb5bfb…

MALICIOUS

PDF

87.7 KB Created: 2021-06-30 00:46:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c4fa3afad0b9444d747a1bc47385950c SHA-1: 1a5f0a01d0847bb3e53b9f510c66f37a2b0d02ae SHA-256: 919b6e250eeb5bfb74c2344c495b902c0579ed6929ccc436174446288305bbd4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document contains a link farm pointing to compromised WordPress upload storage, suggesting an attempt to redirect users to malicious content. The presence of multiple unknown URLs hosted on potentially compromised sites reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608529f441220---kibupunit.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d6b8c730fe---31738576277.pdf
    • http://pospatrans.cz/UserFiles/File/36959431349.pdf
    • https://cooperspick.com/files/29033143095.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7abcd22c8a---guzefivokolifizibaxugelo.pdf
    • http://dichvugiayphep.net/hinhanh_fckeditor/file/6348448715.pdf
    • http://nieruchomosci-swidnica.pl/userfiles/file/wikemipeperemu.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c65ebfa0f60---fapipagilezavupuwosusonu.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2b27ce809---21482747298.pdf
    • https://ehotelgateway.com/bot/ckfinder/uf/files/vudopujemekavatej.pdf
    • http://henri-ruch.ch/doc_pub/file/96350413933.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160941d8752ffa---fukupojot.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/shctetipfgun7dqs55h7qkg9c1/lenimujijituwijiz.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/lpl8ob4k9j6olonil7eik9d8s5/4958618645.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/d9e836d50b60d43f4a369bb563589479/93457790023.pdf
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/f56a51472bc12cb261cfb58d992cea76/vewupetegufito.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16079680806b18---patekuzik.pdf
    • http://a-kamen.com/userfiles/file/bomegudosamerosopijevo.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0ec597361---ganilurepofozibalidigimi.pdf
    • http://dochoiotovn.com/uploads/userfiles/file/lijujivawikitomu.pdf
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/0e6977c3894a1039a4790c215363694f/21817133986.pdf
    • https://almondzwealth.com/administrator/imagetemp/file/lovemudigoza.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/f9ls3gkc3q90cobm9057l3pa15/59907312126.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=lords+of+the+sith+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f68a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF68A 16792 bytes
font_01_sfnt_off00010e9c.bin
f664533856bd3d6ff81b2a92fa8fa70b6d4f82ecc5dc336c6e7c335abb0bd550
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E9C 17172 bytes
font_02_sfnt_off00013af0.bin
eb1e8d2217e4c70c7ecb341671221dc7b7a9854007cd321bda9a0fc08266ff71
pdf-font-stream PDF embedded font (sfnt) at offset 0x13AF0 10240 bytes