Malicious PDF — malware analysis report

Static analysis result for SHA-256 b99616670114cab7…

MALICIOUS

PDF

70.3 KB Created: 2021-09-26 22:10:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e9131da2eead963d5e431b8e41ef7c9a SHA-1: 7b300d7cc05c098b63cd4b4630745bc8483777c2 SHA-256: b99616670114cab7209a3af3c5853118ff435b741285c9d079471ee6f05d004e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier, indicating malicious intent. It contains numerous links to other PDF files hosted on compromised websites, suggesting a link farm for SEO poisoning or phishing campaigns. No scripts were extracted, but the presence of external links and the nature of the heuristics point towards a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://huntic.ru/uplcv?utm_term=best+free+android+alarm+clock PDF link annotation
    • http://geose.ru/userfiles/file/19006868748.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/58618703010.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/kkp1lk4vh4ubo4e4q0cepsj2l3/turumupebu.pdfIn PDF document text
    • http://trustycctv.com/ckfinder/userfiles/files/tamufibedopiniginodupibik.pdfIn PDF document text
    • https://newtop-eg.com/userfiles/file/80372237623.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/458f0bbadcdca24525ae6b9656c1708a/67454680695.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/bosinujaworizigetaxiz.pdfIn PDF document text
    • http://evergladesharvesting.com/ckfinder/userfiles/files/vuvas.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/10866946149.pdfIn PDF document text
    • https://tainandentist.com/uploads/files/202109100349257273.pdfIn PDF document text
    • http://lejonhund.com/upload/mosob.pdfIn PDF document text
    • http://karcannakliyat.com/userfiles/file/17770642986.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/1140a571f6313658a11a078649323e28/82068373273.pdfIn PDF document text
    • http://ronaldtan.nl/images/photo/97347970021.pdfIn PDF document text
    • http://herningbadintra.dk/app/webroot/upload/files/59671710099.pdfIn PDF document text
    • http://moneymaker-gold.de/files/14599811.pdfIn PDF document text
    • https://fq.ua/images/file/geruwevu.pdfIn PDF document text
    • http://shippingengineering.com/files/ckeditorothers/97105305097.pdfIn PDF document text
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/67514973456.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146b4a01cb81---dorevanunokovaf.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/30577964796.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/dajuxurujup.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/dirivowimerupegag.pdfIn 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://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_off0000afea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFEA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7FC 17052 bytes
SHA-256: 17f21ef8e5bf8d70ce3873eedc11f129bb86b545533db5744e8b8361df359d71
font_02_sfnt_off0000f34a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF34A 10780 bytes
SHA-256: ce60ecf511ec6a0443eb2d3d29444bf0784ada158bde71d40c4b8a2e603448e3