Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf751f791b9a03af…

MALICIOUS

PDF

81.6 KB Created: 2021-09-02 03:23:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1ae8ed95ec5797f7e509e7ee9e7d0979 SHA-1: eb0b8be944f92123dc07e6af459f6a0ea7cb3156 SHA-256: cf751f791b9a03af2bafb1ee9a12634c804a19215d42df8cb9af6cd95b146c0e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute further malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://too.kg/wp-content/plugins/super-forms/uploads/php/files/009ca47d613acd2a788b899c70ee4095/nutokomoxurigeroxax.pdf In PDF document text
    • http://danieldesignpro.com/userfiles/nafisexalakejubo.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b37c258b78c---29325289044.pdfIn PDF document text
    • https://unaizahic.com/Files/files/weguwibo.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7c8d0ebeda---videfalesebejugimox.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/54330973729.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/ed0a92aaf456088552cb56f5c8a60e35/20345419780.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/17749001019.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f0d3730556f.pdfIn PDF document text
    • http://fred-robin.com/ckfinder/userfiles/files/pipejakebose.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/jidodisowozuvomerapugan.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ac993a2b8---69007290092.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3592ed98f---pafijavapufuwibabolu.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/vovko6u9vh9qtrvmq77urdtl9o/ranazapibep.pdfIn PDF document text
    • http://dzirerealtors.com/uploads/dizojopazo.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160dfa9d741817---63809197114.pdfIn PDF document text
    • http://reklama-kemerovo.ru/files/files/givagutusagemik.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/00e31d88c8c89e1034bc873b7d6934ab/salegutib.pdfIn PDF document text
    • https://madeirashopping.com/userfiles/file/davanizinozak.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/d75ef6b2b5b65fb2409a22c98243595f/57581310757.pdfIn PDF document text
    • http://newshop.jp/archive/file/31190560293.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/57030419621.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/zizedafejitewamid.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/roboxazapodivelitikubezuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=iptv+smarters+for+android+apk+downloadPDF 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_off0000d8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B8 16940 bytes
SHA-256: e07cbe20379e62ddb387e85cab4254bab6797be17a1cedf34da9adacfa9c0868
font_01_sfnt_off0001048e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1048E 10852 bytes
SHA-256: a7796e9233db61b4d92de21cb069e5d080e31d765ebc0374773d32d8700b2f38
font_02_sfnt_off00011dad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1