Malicious PDF — malware analysis report

Static analysis result for SHA-256 8857b1deed53f45a…

MALICIOUS

PDF

94.0 KB Created: 2021-07-06 20:13:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: a41da72296d095fb928bd11609eaa99a SHA-1: 09e56fd836fb760c08b80e7ce54d40dce8252cf6 SHA-256: 8857b1deed53f45a1be4c0ea64f00421b74cd2a440fe4ae9740b45bd77fa0a29
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the link farm heuristic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16093995e4be43---6289404196.pdf In PDF document text
    • http://eurogeographyjournal.eu/admin/fckfiles/file/97955024575.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/52456170623.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade63920381---35080275375.pdfIn PDF document text
    • https://menuiserie-sainte-anne.fr/userfiles/file/dogoluzafurumilemufeg.pdfIn PDF document text
    • http://konemara.hu/userfiles/file/melupupanararimi.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/meqct3mbkcdgmhsgbumk5jcs12/13966645685.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16097755d21a3d---zunaxukenokofuwato.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/76868136476.pdfIn PDF document text
    • http://ks4073.com/file_media/file_image/file/769550333.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079dd4259afc---67424863190.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ebe4a4616d---153854992.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///beduwefi.pdfIn PDF document text
    • https://capital-tic.com/upload/ckfinder_temp/files/20210628141026.pdfIn PDF document text
    • http://royalrep.com/userfiles/files/42740189039.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/45632020992.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfffde44f5---papudoterixerodomonubu.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c212f35b5a1---sewivegusejuzipomopuwure.pdfIn PDF document text
    • http://msinternationalbeautypageant.com/clients/8/8c/8c0f0497d7166b07b5568c04be8084ca/File/48492009441.pdfIn PDF document text
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/wasisadovebewanoma.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160803ab222a4a---wakudezelilipaxewe.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/e4t0bud9qq89tltii0c6a1e63l/16058079707.pdfIn PDF document text
    • http://bagumul.com/file_upload/spaw_upload/file/20210619221816.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/75685194530.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=calculating+the+entropy+change+for+a+phase+transitionPDF 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_off000109f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001220a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1220A 17696 bytes
SHA-256: 1687d56bd8833bf4e3b328500314e1faa6be12782a4320fe1500fc8bfe29f46d
font_02_sfnt_off000150b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150B0 11004 bytes
SHA-256: 5cc0fa0dd9f84f3c66b3c035f9faef5308d3c3379f725b783529024904ae01f7