Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cd62f362681db87…

MALICIOUS

PDF

83.2 KB Created: 2021-09-14 05:00:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: dc61db8046a75176146e1705b437a46c SHA-1: 134398a6acb4776c9370841ffd6b414494bc8ce9 SHA-256: 3cd62f362681db87768f00e0f308ef66a145e5840eb356708ddd3a7ee0f7eed0
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress upload directories and disposable hosting, suggesting a phishing or SEO manipulation scheme. The document body was unreadable, but the presence of numerous external links and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest the primary purpose is to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16133a5970eca7---sojurixekuzixuzawaz.pdf In PDF document text
    • http://taiwan-casters.com/userfiles/file/35083105083.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/34858085163.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/jebofajuj.pdfIn PDF document text
    • http://gsxr.hu/userfiles/file/noxerivixejanixuxukuvofef.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136fe07b3c10---poxabuke.pdfIn PDF document text
    • https://www.antoniopopolizio.it/ckfinder/userfiles/files/66930495612.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/6172874560.pdfIn PDF document text
    • https://peintures-descours.fr/fichier/files/nigunoranaz.pdfIn PDF document text
    • http://k2plusinterior.com/userfiles/kopeno.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/tuxejijuzuzapetokuvuvumog.pdfIn PDF document text
    • https://samsungdvm.net/upload/ckfinder/files/nujikovexiro.pdfIn PDF document text
    • http://labradory.pl/file/rowonib.pdfIn PDF document text
    • http://ituor.ir/basefile/chartermeinfo/files/8817426087.pdfIn PDF document text
    • https://bnbcostaverde.it/userfiles/file/najikekabajiraj.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/biwasumujowizironuka.pdfIn PDF document text
    • http://farmaciafoglia.eu/userfiles/files/96774767489.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d37d8dd41---74736852538.pdfIn PDF document text
    • https://apra.pl/files/file/lavuvupefewokotedodop.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa0a4ed300---91703810946.pdfIn PDF document text
    • https://frisch.ro/files/file/toxeniwuve.pdfIn PDF document text
    • https://coverline.ro/userfiles/file/sudalotanol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=spider+man+2+free+full+moviePDF 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_off0000dda9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA9 10752 bytes
SHA-256: 139775e88a5ea6428200138f0ffc690001c749841c4ca0ece0923980aa262b5a
font_01_sfnt_off0000f660.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF660 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E72 18956 bytes
SHA-256: 469cefd93d37544ab66c2932c994347aad0fe51a9b3355b93c35bb808c5630ea