Malicious PDF — malware analysis report

Static analysis result for SHA-256 839de169cde2d947…

MALICIOUS

PDF

83.0 KB Created: 2021-08-15 11:49:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f39c6478c137ed3479965436d2e00553 SHA-1: 9da0cdad79df6fb5064eebac47001a94092c87b1 SHA-256: 839de169cde2d947825c9e5aec898bb86423708c490b728b4cd7a88d3513eca1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc0ad76caf---lobeluve.pdf In PDF document text
    • http://flexa.cz/docs/file/jorafewogub.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/83907725549.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/77269250309.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c4e3dd72fc8---29862320277.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/89989765740.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d1aced4bec2---90630857892.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/a37af0b252956cc29fab4698f20c6724/wasuvawijubobejaxupedotip.pdfIn PDF document text
    • https://simplehome.ro/ckfinder/userfiles/files/52070846921.pdfIn PDF document text
    • https://illinoisfiscalpolicycouncil.org/app/webroot/userfiles/file/rakogizepexud.pdfIn PDF document text
    • http://hzdsbg.com/uploadfile/1622355729.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/bofon.pdfIn PDF document text
    • http://thegioituigiay.net/uploads/files/pulilekofunenugigojemapib.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/49818998596.pdfIn PDF document text
    • http://newfieldclassof1982.com/clients/6/69/69e49ffade321d977af769e13f9f004b/File/66684294135.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/reronufipojuwak.pdfIn PDF document text
    • https://keongracun.org/contents//files/badaxedewatadiridomubod.pdfIn PDF document text
    • http://www.anieliasfx.com/uploads/textareas/file/82867557271.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/60880535481.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/wakikikusatapupujamenalon.pdfIn PDF document text
    • http://olddieselparts.com/ckfinder/userfiles/files/19371670709.pdfIn PDF document text
    • https://charlesstreetvideo.com/userfiles/file/wadujevowinegiw.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a019e64625f---nubeluzejezafunajonoja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=life+and+death+stephenie+meyer+summaryPDF 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_off0000df8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF8F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A1 17464 bytes
SHA-256: 1f885cb93c7d74de3486db7bf63481eddef67121c4812352a8e03f8de3bc734c
font_02_sfnt_off00012558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12558 10768 bytes
SHA-256: 5ec75b3acac192ac1ac057de51d48a7d3d34d5dd072eaebf921a5d7d075b7e63