Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1b15cbf681d63c8…

MALICIOUS

PDF

83.3 KB Created: 2021-09-04 22:08:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 277a88e472fa8148eea3c7bc35be60e5 SHA-1: 1c0703c9bd6f1df1fdccf1a38b1f64a89920f264 SHA-256: e1b15cbf681d63c84884e550ca2fb371feed98087920fa2463caeef71c3400b4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites, suggesting it functions as a link farm or redirection mechanism to distribute further malicious content. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160fa0eccdb596---bezufekadeginak.pdf In PDF document text
    • http://dachastyle.com/userfiles/file/35446562795.pdfIn PDF document text
    • https://beauti-full.ru/uploads/files/miguvezapapalusoz.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/80704675335.pdfIn PDF document text
    • http://auldskoolrocks.com/clients/878384/File/73839864784.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/b739a40d28fc5bc3e1f69f12cedace3c/39619548277.pdfIn PDF document text
    • http://frankifoto.com/uploads/pages/files/57140805808.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085ec754bd14---85295926914.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/lupegosesasemukoxu.pdfIn PDF document text
    • http://pozitron-s.ru/userfiles/file/lidutezafitobikas.pdfIn PDF document text
    • https://tedvandergulik.nl/userimages/file/nixopatezelafaluxeduk.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user///file/_0722316001620793577.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/95300233532.pdfIn PDF document text
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/topatajojokevusuwani.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160962ecbd8227---vevalo.pdfIn PDF document text
    • http://accronline.com/userfiles/file/57949044535.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/34607512605.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160705cc9e5a1c---64475089256.pdfIn PDF document text
    • https://lienlacanien.com/img_pages/file/37876430049.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/0dvm5h79r33fmuh26c8v539h47/watovuputexuwepadolosevap.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/tosog.pdfIn PDF document text
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/d4870cf79d92ae9fe77bf99052163638/42471759607.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/begojavejak.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d401894a043---32449536330.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/qm8tcgfrqf613ruvhsr31b0msc/topubusepazamevaruju.pdfIn PDF document text
    • http://gabortech.com/admin/file/xonuvotupazibap.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bizuguzesekenemaxokob.pdfIn PDF document text
    • http://eurogeographyjournal.eu/admin/fckfiles/file/45564360102.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=yuvakbharati+english+11th+guide+pdf+maharashtra+boardPDF 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_off0000d92a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD92A 11376 bytes
SHA-256: f5b1290097654557293ad90cd7cf60a96fa4c6fcd33e20cbbd1d7822dd7e011a
font_01_sfnt_off0000f374.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF374 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B86 19320 bytes
SHA-256: 4041fed9b64b7ab9e68ea8a6f8fb2d358c989a79dcc668543e14c43b27d4e49c