Malicious PDF — malware analysis report

Static analysis result for SHA-256 617759b1e5c5f335…

MALICIOUS

PDF

91.6 KB Created: 2021-06-12 19:41:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: d025b0da42c84aafbe20a2bb17ccd1e4 SHA-1: 90b7744bfdbe74c5c3fdcb8b7d2e9ef8da944c24 SHA-256: 617759b1e5c5f335b296ff3091906075e60a02b220ef82a3054a8deab211cc5d
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, indicating malicious content. It contains numerous external URIs and link farms pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of these links and the overall structure strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ketchas.ru/uplcv?utm_term=how+to+feed+chicken+stardew PDF link annotation
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/a3329ed1d1b3d8a3ca1f8e56896e27cb/mekevebejejawevevib.pdfIn PDF document text
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/fb256a6efcde1645ede4a3f6fee3d2bf/31210651439.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210514123223912.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/tafag.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160782d47bdf82---77535179094.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/724emq6k3it6vsf59ovmjrrk1s/buzemazobufapozakekibi.pdfIn PDF document text
    • http://donkaew-furniture.com/ckfinder/userfiles/files/jupadubujod.pdfIn PDF document text
    • https://clifestyle.net/uploades/userfiles/file/fetofobadiso.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a002a75fc11---futuwolupeke.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/0b04vf38r0mnlj39ogp67ice1a/85003901647.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/1485720070608a8df8e7f06.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/444dd2ba243ab04d50673c371b2f88e0/23465594322.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a908b08b68c---tedujunigojovasenewur.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/39dcee10936c75e73b1e700245f6355b/35741858600.pdfIn PDF document text
    • http://weifong.tw/fckimages/file/58507434797.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b8936c443---zejirubimiriwigotatajik.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607578c793f95---96688482153.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/8c08m26nhd202lc6dfl6qaeme0/15601988005.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000127df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DF 5192 bytes
SHA-256: 7ec6a640cd04ec1972498c2aebaa2a1e044b62ccbdd67d5de44ed102f8f319be
font_01_sfnt_off0001399b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1399B 11292 bytes
SHA-256: 65c80055a2dc5dd9a13ec1dbebc8cffdb2acbbf77a8ccd99f2d59d84832ee394