Malicious PDF — malware analysis report

Static analysis result for SHA-256 f305ac573e82b3ec…

MALICIOUS

PDF

73.4 KB Created: 2021-08-21 06:07:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 99674b741dafc15426a88948faf8336f SHA-1: d7ab29ae4fe3e7472826b162051fc2496b051440 SHA-256: f305ac573e82b3ec097a3d73c21a9f1de2daa815c9ca0d69a6b638217acf76c5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://vocembalo.ch/userfiles/file/fibunek.pdf In PDF document text
    • http://wildpflanzen-planung.de/file/15709820082.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16076f524ce83a---51620697959.pdfIn PDF document text
    • http://laclonghotel.vn/upload/files/38553932688.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b65b36010c0---xoxekivipanapefosuw.pdfIn PDF document text
    • http://project-st.ru/userfiles/file/favotidowugizivaluli.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/35336388970.pdfIn PDF document text
    • http://silverleafspa.ca/clients/10619/File/41536135134.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/pojewegi.pdfIn PDF document text
    • http://myjobcareer.net/userfiles/file/2021052206481573499.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093a41c28a7d---36130251056.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160f10982ea7fd---wafolewasamodadubawewugit.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/foniwujasugo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8ef563dda2---84145929937.pdfIn PDF document text
    • https://carolinevlieghe.fr/images/file/dabasisamibixaji.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/puravexavajorekuwe.pdfIn PDF document text
    • http://demkapi.com/resimler/files/vusimexibere.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/0gtkoc4lbaud0oitqf3d9djk8l/wunixiwodo.pdfIn PDF document text
    • http://artikos.pl/userfiles/file/79291611522.pdfIn PDF document text
    • http://sbsinternationalschool.org/sbsisnew/userfiles/file/dakajej.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/kirisibosudibi.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160c50f16b0159---13290153865.pdfIn PDF document text
    • http://sipsak.nl/userfiles/file/73672433405.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=would+i+survive+the+hunger+games+quotevPDF 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_off0000bb7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB7F 16836 bytes
SHA-256: 6189435fa172916e2c8bf262c930cc4a1b55f8c152f029a5c1960b12c683a8bc
font_01_sfnt_off0000e74a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE74A 11000 bytes
SHA-256: 0b7671c30bc14a58a11c671b272e5d06ce97160a1cd02f77590d4735e9ab8400
font_02_sfnt_off00010027.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10027 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1