Malicious PDF — malware analysis report

Static analysis result for SHA-256 def7c97983df8d11…

MALICIOUS

PDF

93.8 KB Created: 2021-07-19 14:28:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a51030a97c8e01b7955dc1bd00b81fdb SHA-1: 0f618ff4260c71ca0cd50cf5dd61d5fd3fe841b3 SHA-256: def7c97983df8d11176052fbcf281735f864a0c42fe14d8c96845a8bdfa81f5a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Several heuristics identified the PDF as a link farm, pointing to compromised WordPress upload storage and disposable hosting, suggesting it's designed to redirect users to potentially harmful sites. The presence of numerous unknown URLs further supports this, as they likely serve as part of the redirection chain or payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160cce17a2750a---70903978538.pdf In PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/6c6750bf63799df37034371c3be15d66/jidilenipuw.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/28758952140.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097a21d3431d---mezelojezewumoxunuruz.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/gajuruz.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/77078768350.pdfIn PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/31f6b5a40da816bda1a39bdbb06ae0bd/53417684755.pdfIn PDF document text
    • https://goodline.by/userfiles/file/518527106.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/i6112d3tm1vofl1m4vgliui187/13273470453.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/75379838655.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/nadufenolabekojiraxa.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d541f2663b---57292347565.pdfIn PDF document text
    • https://dadesigning.com/daduserfiles/files/bitotowimojifubomod.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160851841535f3---karuvam.pdfIn PDF document text
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/73919652781.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb035034ae---kotavarikasib.pdfIn PDF document text
    • https://amblamy.ee/upload/file/bidikapomilebirati.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/16321654428.pdfIn PDF document text
    • https://zabulgaria.org/userfiles/file/nejawasezunidunilawuguva.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/89adrrnr8ktniaksdvnmut2kbp/supokexujaranapagemigi.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b41642a09fe---webuwexekilumokisasojifan.pdfIn PDF document text
    • http://masseydogs.com/clients/f/fc/fc2e217ffa4851e49ca3cd921a15cf41/File/25629160598.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/0889803005cc9409daaca275ac40eb98/rapemewilolixedawado.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210705_CDECF5F7F145DBAA.pdfIn PDF document text
    • http://limeitec.com/upfiles/editor/files/lepin.pdfIn PDF document text
    • https://detectiveoffice.net/userfiles/file/78484805495.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/9c8322c1006f803b6a2769d277cbff23/27960154112.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=full+moon+and+labor+contractionsPDF 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_off00010c87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012499.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12499 16908 bytes
SHA-256: 17d0b4be671c91b362aed51428f5ae4d4ef4a47d393163b1e84a3a5726f352ba
font_02_sfnt_off00015027.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15027 10616 bytes
SHA-256: ca5730b58f92bdc1cc7086d726786ff21ef6c87dbdc5be601060d8e4b74ccd35