Malicious PDF — malware analysis report

Static analysis result for SHA-256 7eebb127100ea85c…

MALICIOUS

PDF

82.6 KB Created: 2021-09-18 09:50:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3f705b0d85b90fa39f0852ecc6aa3510 SHA-1: 367e958aad807075dad4b5f7739de5348e69eb8d SHA-256: 7eebb127100ea85cc22845aea95ea46d9c0dd42176ffde5ad01e0beab4d4ad77
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to potentially compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly indicated maliciousness, and the presence of external URI heuristics further supports this. While no scripts were explicitly extracted, the nature of link farms in PDFs often involves JavaScript to facilitate redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://pistant.ru/uplcv?utm_term=android+extract+apk+from+installed+app PDF link annotation
    • http://xsteelstock.com/d/files/fenunisurijidore.pdfIn PDF document text
    • https://agri-mal.pl/userfiles/file/67738732043.pdfIn PDF document text
    • http://daiichibus.vn/uploads/news_file/degufovowa.pdfIn PDF document text
    • http://phutungquanghieu.com/app/webroot/files/ckfinder/files/56347820675.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/sapeluwutikipi.pdfIn PDF document text
    • http://zatuchlina.cz/upload/file/tatit.pdfIn PDF document text
    • http://www.pibmg.com.br/ckfinder/userfiles/files/files/zijoguviwesu.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/99817577935.pdfIn PDF document text
    • http://avvocatogiuliani.it/userfiles/files/vomazijilafifevezatogud.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/3db166a90011a9fd33bb21dcad4a77bd/vinebematami.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/pumuga.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613e0288aee28---14696939970.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b3fe25058---1068437391.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1614550379f569---tajelemuzumosikofimibiba.pdfIn PDF document text
    • http://ambulanceservice.pl/userfiles/file/10627798642.pdfIn PDF document text
    • http://website-design-company.in/dev3/damodar/ckfinder/core/connector/php/userfiles/files/vekolep.pdfIn PDF document text
    • http://www.chubsorn.com/file/files/foxorudiboziwabu.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ba62cbe2e---favox.pdfIn PDF document text
    • https://eksiliotomotiv.com/upload/ckfinder/files/30977358772.pdfIn PDF document text
    • http://mixline.ru/img/lib/file/fanapitewofik.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/buxonilifero.pdfIn PDF document text
    • http://rbtyutj01.com/userfiles/files/sokuzobevubim.pdfIn PDF document text
    • https://refakatci.net/userfiles/file/95679381586.pdfIn PDF document text
    • http://zezoalza.com/ckupload/files/84020166308.pdfIn PDF document text
    • 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_off0000ddda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5EC 17460 bytes
SHA-256: 235c86e53a9538d5fd6328bfe15ae8202055f670d2cbc35dc2d7e370976c2107
font_02_sfnt_off0001233e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1233E 10956 bytes
SHA-256: f2a7aa241559f03313545f1b9fe127163baa15b34ac52fcb2b0ece3bb850f5f8