Malicious PDF — malware analysis report

Static analysis result for SHA-256 d357ff72db413fd0…

MALICIOUS

PDF

83.4 KB Created: 2021-09-08 22:26:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 02aab1507feaa14d9ad63f9c1be0f720 SHA-1: a91dd795c20d997968e34617f1cc6eca733bec6d SHA-256: d357ff72db413fd08a780acf9a5cf261c6e4ba292b46181ecdaf4766d479ccbc
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The embedded URLs, while some are confirmed benign, are part of a broader pattern of deceptive linking.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://bestbelly.org/content/files/files/12374960411.pdf In PDF document text
    • http://bctlorraine.org/userfiles/file/gulakawoxi.pdfIn PDF document text
    • http://kuhomania.ru/ckfinder/userfiles/files/vukab.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/jutudef.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161373a634230b---17720680437.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/xobaduwugorozas.pdfIn PDF document text
    • https://giridhareye.org/ckfinder/userfiles/files/48926528220.pdfIn PDF document text
    • https://rux-thai.com/ckfinder/userfiles/files/tuguweveza.pdfIn PDF document text
    • http://hiniceshine.com/upload/53786099045.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/65484478474.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136fef7e8d95---57328015639.pdfIn PDF document text
    • http://bsinteriordesigner.com/userfiles/files/tiwenemew.pdfIn PDF document text
    • http://yourtruck.be/upload/ckeditor/file/pebazufizolumi.pdfIn PDF document text
    • http://allmedicus.com/userfiles/file/vugujekiwavogonajumelexa.pdfIn PDF document text
    • https://sanghvicranes.com/staging/media/55178968783.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/a07a45382313089dc93768459142e67b/29264626712.pdfIn PDF document text
    • http://memsports.com.br/admin/libs/ckeditor/ckfinder/files/14197573425.pdfIn PDF document text
    • http://think6.net/ckfinder/userfiles/files/20210903135952.pdfIn PDF document text
    • http://design-klasse.de/ckfinder/userfiles/files/kixigupifepikof.pdfIn PDF document text
    • http://vincitydata.com/uploads/ckfinder/files/vavuvabadeviroke.pdfIn PDF document text
    • http://35ju.21tg.cn/uploadfile/ckeditor/files/76344565225.pdfIn PDF document text
    • http://porpora.group/imagenes/imagenes_contenidos///fipigo.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3ad5a431e---nusinebikotoxad.pdfIn PDF document text
    • http://dinhvi5s.com/images/newtech/files/80214156381.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=game+download+ppssppPDF 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_off0000e17c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE17C 10388 bytes
SHA-256: 8fcb91b907d7866f5795cf176cae9e22c4a7727580e178987063c835d29e3b3c
font_01_sfnt_off0000f907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF907 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011119.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11119 18004 bytes
SHA-256: 91e3335092ab2439b9015d2cd23706e16011c890db0ad5d64b5cf4d005dd7327