Malicious PDF — malware analysis report

Static analysis result for SHA-256 99cfae9231abfd0e…

MALICIOUS

PDF

73.5 KB Created: 2021-09-08 14:54:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5af20b836c5a84734abfc4234a02e4d0 SHA-1: f61b146af04fb0c09f9b76b2405e07e10cdd0f29 SHA-256: 99cfae9231abfd0e24cfc5c27578447e59770c9df74f2d7cb92c2c9f191f7c23
126 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it's part of a link farm designed to obscure malicious destinations. While no scripts were extracted, the presence of numerous unknown URLs points to a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://dpsnowodworze.pl/userfiles/file/bigiwezida.pdf In PDF document text
    • http://damvua.com/damvua/public/images/files/zikej.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/towejexetutodazowitukewa.pdfIn PDF document text
    • https://hanedantoptan.com/upload/files/lobututiz.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/74bf9c5d4ed5342d80c14b5c34a7c4f2/92007948769.pdfIn PDF document text
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/13864519475.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/simonepowa.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/80391447403.pdfIn PDF document text
    • https://anhhuynoithat.com/asset/files/13027356326.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/62675008287.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/gufavukadazavipinujonube.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/fidojogufojixewufuvetawaf.pdfIn PDF document text
    • http://ceresasrl.it/userfiles/files/zabekaraxowagezegovutijem.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/gimuxijefagasorisor.pdfIn PDF document text
    • http://emke.hu/uploads/ckfinder/userfiles/files/buluxelixusafoduxi.pdfIn PDF document text
    • http://whatdwellswithin.com/file/42921114221.pdfIn PDF document text
    • http://getvisa.ru/images/File/selapusifinizejuvitov.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/tigozufazago.pdfIn PDF document text
    • http://rapet.hu/files/61232669688.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/161362fdd79678---pukiwijifosenezuri.pdfIn PDF document text
    • http://hairfibers24.com/upload/file/45788026626.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/38639106143.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/75337174588.pdfIn PDF document text
    • http://coachhouse.info/assets/file/31036216559.pdfIn PDF document text
    • http://trovas.com/userimages/32801501575.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/pobefivizimibopupafite.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=uk+map+outline+pdfPDF 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_off0000bdaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C1 16580 bytes
SHA-256: 63df73a30d5c13e8e7da35c83bc826e5058b0b86b7589ab49b4215c24354eaad
font_02_sfnt_off000100d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D6 10592 bytes
SHA-256: 7b556d4538848142852b7cec16e65376187696820e81691d9d1b55f8884194a9