Malicious PDF — malware analysis report

Static analysis result for SHA-256 d33e13f57a4c3622…

MALICIOUS

PDF

86.0 KB Created: 2021-06-25 14:13:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea983d7b0936be66d4b5687f6bb89c00 SHA-1: 36e7de4f84d8272180d0b5656b2579aa82b9908e SHA-256: d33e13f57a4c3622f23b1ff48f3b76707e697c35d8357db22a674724313c4fb1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It contains numerous external links, many pointing to compromised WordPress upload directories, suggesting it functions as a link farm to distribute malicious content. The document's structure and embedded URLs are consistent with a phishing lure designed to trick users into downloading further malware or revealing sensitive information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://archism.ru/uplcv?utm_term=textbook+of+osteology+by+poddar+pdf+free+download
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/idpd9fmj9snk3cnpae9a3dg947/dewofajonuzimobujirug.pdf
    • http://symbioticlifetech.org/attfile/fckimg/file///2021050711122_615684438.pdf
    • http://wignaccent.com/FCKeditor_2.6.3/userimages/file/20210617180535.pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160746b3b85055---pagedisiram.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078c9150cb1c---2934880261.pdf
    • http://ptairsupply.com/userfiles/file/26884422779.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/866685e27e04aedcec6f9574fb09759a/vunazugafapufivimikefiduk.pdf
    • http://hacoauto.vn/upload/files/76590484634.pdf
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/66d77e3b14547eaf3b0dec6297676b30/melemujabi.pdf
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/4d25e49155b1fd4b02377f49bcff851f/bujaxoku.pdf
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088b88a346ef---jevizilolasivabebalunom.pdf
    • http://www.peretprod.ro/content-images/file/78874043800.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608671cc2e70e---gafudawotasiv.pdf
    • https://planet-pvc.com/upload/files/26316694589.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/835c34cb5343799387e9bc120812c8ea/jijitibakiwisozivotida.pdf
    • https://binarbaidfabrication.com/public_html/userfiles/file/37508749475.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ab419f548---37754568618.pdf
    • http://sillajen.com/fckeditor/_upload/file/jabakev.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e98d.bin
5e09cb7d21fcbb8b1f4a4e2d267d56b7e014867d42849d584f618687f28e791d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE98D 17976 bytes
font_01_sfnt_off000118c3.bin
c83a45d17f3c79b14f1779f3f7cae2062b9e5bde0b343cee4b742c3096c59961
pdf-font-stream PDF embedded font (sfnt) at offset 0x118C3 11080 bytes
font_02_sfnt_off00013272.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13272 16792 bytes