Malicious PDF — malware analysis report

Static analysis result for SHA-256 53fdbe23fec2f265…

MALICIOUS

PDF

96.1 KB Created: 2021-08-14 17:42:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 875b2b5630e99f0365a56e91f38c0524 SHA-1: 55fe9fc7e5ad30b55ec2daa224c83028e5161bf4 SHA-256: 53fdbe23fec2f26587b99cb548de34e3937326093393d9bae7c6534aec6b3e35
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple links to compromised CMS uploads reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9896

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://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098b58559769---31709745540.pdf In PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/m4k1398f4m5v8cp4f87a75o53r/wepidupevinonipimes.pdfIn PDF document text
    • http://thoitrangvabaoho.com/Images_upload/files/39694640949.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/leraniv.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/sawasoxi.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/mosibugowiz.pdfIn PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/p0n0f815h9f236ql8m8c9mu4ts/bifupepo.pdfIn PDF document text
    • http://porpora.eu/imagenes/imagenes_contenidos///xuwabekefobazapojuditi.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/5010ebb2ecfafc206c555b071759783e/87379382061.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/1331016445.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094a3958fc1a---96693259312.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/sjiuq06amjklcctu7lvuo9ob7k/sebaxivajerujuxuge.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/sosopekulofinexopurin.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a043c1bd6---56610396408.pdfIn PDF document text
    • http://fedoro.ru/upload/file/fatom.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/11k89pf9bcv8h1qej1ok9hf4nv/dinejivalezativebexi.pdfIn PDF document text
    • http://nomaquito-travel.com/editor-images/48961114653.pdfIn PDF document text
    • http://kimbuunguyen.com/uploads/userfiles/file/82134795432.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1609d56f1a6572---7877631456.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/4d8gndmf319pfp59eas7fi43s0/15727532924.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070be8a27e2d---vujinurevurefovofinabeme.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160daddc068de8---sofezezuriwagoxatil.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/metokimizumokufop.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/j5v9att1rn0mngdcrejib8teis/kedawokirivarebigutiseg.pdfIn PDF document text
    • https://pmeds.us/userfiles/file/nujabokikudasuzarumik.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/borisodajusaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=shl+direct+inductive+reasoning+test+answersPDF 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_off00010e9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E9A 10976 bytes
SHA-256: 53769b94a308c17111580c6209d74261ab05dbcaa2bf636f85dd153fc11fadb5
font_01_sfnt_off000127dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DD 19312 bytes
SHA-256: 2011f16092caaf06a60398d20f65e38fb6db7efe17825382111fca3bd20141ea
font_02_sfnt_off00015924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15924 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1