Malicious PDF — malware analysis report

Static analysis result for SHA-256 57a4d386330e4e07…

MALICIOUS

PDF

88.1 KB Created: 2021-07-17 14:38:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f9a8cf92025450ae9a992df64b17745e SHA-1: e8f4e77153653074d50773a157aa8b8bfbfa7eb1 SHA-256: 57a4d386330e4e07caae505c5979fb68a0e20ba675ecd6abbd7923e1ebddb423
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or phishing pages. The document body is unreadable, but the URL structure suggests a link farm designed to obscure the final destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c02ace5bb8---66185876279.pdf In PDF document text
    • http://www.ochoadentalcare.com/tacgestorcontenidos_ochoa/documentos/file/In PDF document text
    • http://naplesredeals.com/userfiles/files/92690415510.pdfIn PDF document text
    • http://crackershrimp.com/file_media/file_image/file/41465118514.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b46d5a7607c---34889764815.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160b59417bbeeb---48730511032.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/7987496247.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607357ae54269---maxakijepagatek.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0c7906a2e---50974187721.pdfIn PDF document text
    • https://mollis.rs//files/8566349850.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16087b4776dd91---faloguzezesafofakure.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/829aeaefa3d7244ca120ced82c835c6a/laluremivu.pdfIn PDF document text
    • http://darec.sk/files/files/jetawikejitivupekosubov.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/16076f49657504---goxiwamawu.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607916599ef55---xumubijositapamexuto.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/keragidiwamiv.pdfIn PDF document text
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/22035817582.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/96520965f80dd186c7488dea5eec771a/zifenu.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/3918ecdf7c69829cce1f0018b2f2ecae/24474546431.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/a8a7824e86640c059ef37499fcfd9dbc/9982199118.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/2ec1db9ae84ec6c91703244d411c89f8/fonepinavov.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/3e0a31dfda144ee69cbef07f07c267da/90076236514.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160bf2261d7a8f---33008840524.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac37f05d447---49234681396.pdfIn PDF document text
    • http://burrburroughsfamily.com/clients/55468/File/28530168074.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=element+table+1+to+20PDF 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_off0000f447.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF447 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C59 17608 bytes
SHA-256: 346959f4c0375af8e826f0c05a390911dfacdeba92e080842b1e93f6b2b30ee4
font_02_sfnt_off00013a61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A61 10328 bytes
SHA-256: 775864d3e2738bf3d62e3b2c682dd29b99911b29b1f1c8f435cf526521af8075