Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7a5982c10497a04…

MALICIOUS

PDF

70.2 KB Created: 2021-05-09 21:33:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fcb7b2748456f8925a8d030f53e44f77 SHA-1: 5d81b7e3b6e75fc8261e5c112067f21c18409dcf SHA-256: a7a5982c10497a048b8dc214953ff4e3134da40daaf8084b2077f49cc78565d3
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs point to compromised websites, suggesting a link farm or redirection scheme to deliver further malicious content. The document body is heavily obfuscated and unreadable, indicating an attempt to hide its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607870591e488---jonebudabuz.pdf
    • http://apexnepaltravel.com/userfiles/file/37176347452.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc65a965f0---vegetakugogabugodub.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160912031759cf---20166558075.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/6b51104561961035344d56bb7864d7da/nuvaxaxenopinesol.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/073bcbaaa7281bebfee620089ae8e031/27729446559.pdf
    • http://93564497.com/userfiles/37570043605.pdf
    • https://nhathuydesign.com/wp-content/plugins/super-forms/uploads/php/files/073r7rulguifdb2jiddhg2o8r9/xitefewigesevuvamiweka.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078a68ee3b04---wisurujuxokinosamufeku.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/e0c040da7caaf78e167f81acb02e7a86/xugixetivologo.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/1nbr1bmf47qsuarrmf9dtha6b2/mofupotegutopigisixoduxu.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608722bd4e3a9---geralinebofapixupazi.pdf
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160755ff8eb57e---tipux.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075afefba47c---38117049646.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/06sp32l7gcvudbn5ip2fr55887/duzetejejo.pdf
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/c218c1a86c7ef0f00723c66618426ef0/60247733716.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/o0cdead5lvooqpm5oke5mr2vh4/nokegu.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2254ddbe4---66674288717.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=the+fractal+geometry+of+nature+mandelbrot+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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d19a.bin
82c7b23f99aad836b672594edc3fc1ea1daf1f3be441045789659404c7a10afe
pdf-font-stream PDF embedded font (sfnt) at offset 0xD19A 5584 bytes
font_01_sfnt_off0000e46d.bin
58d224bce1227c72e23422b2f5bb7c89225cfeddae1096a3d45bd4bda5b5b08a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE46D 10968 bytes