Malicious PDF — malware analysis report

Static analysis result for SHA-256 c057abe1df0170f1…

MALICIOUS

PDF

77.6 KB Created: 2021-09-06 11:23:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 246d98696161dd83d1a0e6ddd8c02b13 SHA-1: 424a5c71928b608cc2df91bfa68b69179b2ad0b8 SHA-256: c057abe1df0170f1019dc09424b00c1b0e213e35a4b607b718b02bbeab7c343e
96 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on compromised websites, indicating a link farm or distribution network. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting and pointing to compromised CMS uploads. The primary attack pattern involves directing users to external malicious resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 5

  • 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.la-providence-ehpad.fr/ckfinder/userfiles/files/lukinisubezavizoge.pdf In PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/fupatugubasujova.pdfIn PDF document text
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/acefe0289d668f5ead3ea2c71480f659/kapojulijozixodoki.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607140f3d7681---70331722717.pdfIn PDF document text
    • https://wronba.pl/uploads/wysiwyg/file/kusewoviwirobufisemorosut.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/mn24s80v4ko10ro75t4me812mo/zemubavaweso.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/83874651715.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/16088610b34a18---22069483867.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a792a8a31f3---wigudamise.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210814121100999.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1609bbd6eb2dbe---59814099027.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/3618709063.pdfIn PDF document text
    • http://normandyclassof79stl.com/clients/e/e1/e16d7b8530e96d8d426d6b963c92b0b5/File/1529095467.pdfIn PDF document text
    • http://pengyou-english.com/FileData/ckfinder/files/20210826_F25991F071F362C8.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/85186501176.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/maketuxevasugoz.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1606c968cdd802---vurixadavagopipugo.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16085a071520ca---zavaw.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/kukugogakexazo.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/a73b6340bd571a730a7cf38c3ccef5a4/25985969748.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/21111031177.pdfIn PDF document text
    • https://best-label.com/upload/files/22650598715.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=descargar+libros+de+jaime+bayly+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_off0000c885.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC885 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e097.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE097 18428 bytes
SHA-256: ca214ea0ab66241a0410174b3c329c626ab5ac9ce355c18f65cd1e368e73cd99
font_02_sfnt_off00010f58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F58 11144 bytes
SHA-256: d0a0053a34e9b9674631a197c8a73568fb5e0456d493fbd64be0c66a121a90d4