Malicious PDF — malware analysis report

Static analysis result for SHA-256 20b19be2a8ba3628…

MALICIOUS

PDF

84.9 KB Created: 2021-09-20 03:02:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d13a5d9269a003b6d5c28b735f355767 SHA-1: 6d41b16a979eab381142ef99164e07512d229bb3 SHA-256: 20b19be2a8ba36282f40888edf103687c094c443b7601d617330be7625bc6535
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicative of a link farm used for phishing or malware distribution. ClamAV and ML classifiers identified the file as malicious, specifically flagging it as a phishing-related trojan. The presence of external URIs and link farms strongly suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://defi128.com/userfiles/files/wotiz.pdf In PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/59493734114.pdfIn PDF document text
    • http://bannhuaduong.net/upload/files/zofoweturazejanotifejab.pdfIn PDF document text
    • http://sisparts.pl/zdjecia/fck/file/92541257122.pdfIn PDF document text
    • http://abwferrellpkwy.com/uploads/files/kopurigilipijepom.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/17393040148.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/sufej.pdfIn PDF document text
    • http://uzmansporzeminkaplama.com/resimler/files/31293745106.pdfIn PDF document text
    • https://conviviodihera.it/dati/upload/file/jujizasomukenilaravoxap.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/f39d0e4da9b3c9a652ad8c90ad3935a6/43833200803.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/89950881436.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/kepefa.pdfIn PDF document text
    • https://festacontinua.it/public/file/wukijonoziromum.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138c156e2a86---98373134762.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/katugulefoxomobepeseniz.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/pomagapopelobebobuva.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/fg21fu9r3ac1ltc5i7t9ea3217/97131779704.pdfIn PDF document text
    • http://iphysiology.ru/upload/fejopafesalaramev.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/25321410277.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/92906650451.pdfIn PDF document text
    • https://lyubomiradineva.com/files/file/gewanelipipekowifixuxale.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613551428ebf6---37958694254.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/jegesujuxokezimogov.pdfIn PDF document text
    • http://playeasypiano.com/resources/fck_images/82898716081.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/tivupezubiziruri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=cool+free+apps+for+androidPDF 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_off0000e7c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C3 17672 bytes
SHA-256: 5be52da8c103ebd0ec639290e74984b7009171acc1954c7aad9e16a517242e62
font_01_sfnt_off000115aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012dc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DC1 10424 bytes
SHA-256: f258534ffa6807d602db8b008b8805a985b2d6554bfb87e19599532f2edb94ce