Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8f7a2eeee37f626…

MALICIOUS

PDF

75.5 KB Created: 2021-09-08 12:52:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4f7c3fb76ac8e0842a3ddac76bdf2296 SHA-1: e19c939988f72df89e09a292e05af1c48b89f820 SHA-256: f8f7a2eeee37f62617e955e1c8e8e09c31628799428a7d8d69c34600e8644dd5
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on external domains. Several heuristics indicate this is a link farm, with some links pointing to compromised CMS uploads. The ML classifier strongly suggests maliciousness, likely related to distributing or hosting malicious content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 http://artediapharma.com/upload/files/23517965382.pdf In PDF document text
    • https://diamond-marketing.cz/soubory/31395554255.pdfIn PDF document text
    • http://lifeline-sports.com/files/file/penulonugalupubi.pdfIn PDF document text
    • http://sanalights.com/admin/admin/uploadfiles/file/ramaravewo.pdfIn PDF document text
    • https://firsatpin.com/calisma2/files/uploads/natinu.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/zilasevorazulokero.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/cquccsuqn0ta2ommbgd4eghf01/gexifezadub.pdfIn PDF document text
    • https://beaszemin.com/files/piritusosejazurogafo.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16134566281684---kuzebenigapebewulatinewaj.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/21603763554.pdfIn PDF document text
    • http://icmasistemas.com/userfiles/files/28443767293.pdfIn PDF document text
    • http://winecellarkeeper.com/ckfinder/userfiles/files/pokaruzi.pdfIn PDF document text
    • http://giaydantuongphongngudep.com/images/news/file/tevipida.pdfIn PDF document text
    • http://nhatminhtrading.vn/app/webroot/uploads/files/35455668294.pdfIn PDF document text
    • https://bepxuyenviet.com/upload/files/42926343119.pdfIn PDF document text
    • http://momsystem.ru/public/file/20535912247.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/cf8cbaaacfe06a9aff48772ade55119c/gisalalijixofaf.pdfIn PDF document text
    • http://www.dkmodels.net/ckfinder/userfiles/files/lijanutotejewogidem.pdfIn PDF document text
    • https://marblo.ph/app/webroot/img/files/44852456679.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/9993663664.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/45597beee02d246bc7e489e9003ae87f/99986586806.pdfIn PDF document text
    • http://share-world.tw/userfiles/file/38950683439.pdfIn PDF document text
    • http://studiopiergentili.it/userfiles/files/76852908615.pdfIn PDF document text
    • https://www.ewdel.cz/ckfinder/userfiles/files/21790772246.pdfIn PDF document text
    • https://bushregenerators.biz/userfiles/files/ravujakedogetudizon.pdfIn PDF document text
    • http://suachuamaydemtien.biz/userfiles/file/23446092087.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=the+video+game+debate+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_off0000c3ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC11 16860 bytes
SHA-256: 3428bf09f4a9b2739b080e74a8a7d4c162c3ff40e1d5915985939e65ef916998
font_02_sfnt_off000107c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C5 10696 bytes
SHA-256: 605f30044bbc318e1d6b2388f94bf0fbe62f3fdf56537bced5c5f011bf3df9db