Malicious PDF — malware analysis report

Static analysis result for SHA-256 4afcba4b063e8f4b…

MALICIOUS

PDF

74.8 KB Created: 2021-07-26 19:37:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b61d81c3d8d727609d41b6c36ef24279 SHA-1: 94951d67fbdd34ec8ea4c7d9a59bff97e768bf9e SHA-256: 4afcba4b063e8f4b1a141b01f6369d3760bd4561b147ef622d5df2fdd65bdcfd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised CMS upload directories, indicating a link farm designed to host malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malware delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/f69eb6rv22t8oreriljebek950/jimeximosu.pdf In PDF document text
    • http://cosmickino.ru/sadm_files/99725234172.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16093a6d9623be---85458370291.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/100qftodmcfvbqde63dhhel8eo/82976861086.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609b0c94b4a77---lazajerunegan.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/65582789495.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/036mtf3q97jieunvnnomlkc9o9/zimipavutefupebotep.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa1a42ce6bc---12951365580.pdfIn PDF document text
    • http://fashioneducation.ru/userfiles/file/tewixumodu.pdfIn PDF document text
    • http://bienchidan.org/uploads/files/sezalusejos.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a34f4089399---29484631260.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/4bbbdb4fd11fdc025f7107e1010cc8e1/lugigutudaniporiteput.pdfIn PDF document text
    • http://topoint.cc/userfiles/fckFile/20210702205505.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/d19ee615393cffadd8d426be454b942c/23436612524.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/f0c8aaf75ab5ec5e232efddba4f62435/93858416657.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/00975a8f2c08b70fc234ad70f66d0627/kiburo.pdfIn PDF document text
    • https://abhimaninteriors.com/ckfinder/userfiles/files/65315787499.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/73878046358.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16087633191334---kepetezugeriziwi.pdfIn PDF document text
    • http://kco.su/userfiles/file/juvano.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbd09879495---vukopowubefaferobival.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/1d3182db37bc519e7a3f0bc6336aea0b/xotavapaguj.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/s6krtp9tc0dk7vv4tukhtfrjcf/35417430659.pdfIn PDF document text
    • http://www.haztartasigepszakuzlet.hu/pics/file/58872516376.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a180c176538---gojazuz.pdfIn PDF document text
    • https://ikima.fr/uploads/file/43198454627.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=tai+chi+108+steps+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_off0000c238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC238 16524 bytes
SHA-256: 0db65f5e301d0dde5c993a64c48b3ba9eb26022575b6279fc7e84a054f013e9b
font_01_sfnt_off0000ed33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED33 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001054a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1054A 10692 bytes
SHA-256: bd1a487a3ad738e45fffebfa086bcf60a5f948e98c46dec202fa9d992e67f9af