Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4ef721462150042…

MALICIOUS

PDF

83.5 KB Created: 2021-09-11 14:38:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a5085206b2be29d90c1d06366281df49 SHA-1: 56296d8d043036582123a5747a577629f3a19931 SHA-256: d4ef72146215004243ac42fd87bdecf1bcc6c28b2e92f70e9171b02b6f7c323b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The file contains numerous embedded URLs that point to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

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://catamma.ru/uplcv?utm_term=how+do+i+get+my+apps+to+stop+crashing PDF link annotation
    • http://jenan.com/ckfinder/userfiles/files/29414530659.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/nawimelezalogosovobezefo.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/7246340948.pdfIn PDF document text
    • http://ministerium.pt/files/tubusadasasedan.pdfIn PDF document text
    • http://519pf.com/userfiles/files/68763718215.pdfIn PDF document text
    • http://ingmarcofaedi.com/userfiles/files/13823164137.pdfIn PDF document text
    • http://russia-ex.com/images/blog/file/9150237531.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/18552750573.pdfIn PDF document text
    • http://kroonzuivel.nl/ckfinder/userfiles/files/85278008466.pdfIn PDF document text
    • http://designbyjoseph.com/uploads/File/fugudoketegogef.pdfIn PDF document text
    • http://vivaibonomo.it/userfiles/files/52626127581.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/55963562920.pdfIn PDF document text
    • http://hb-hospital.com/file_upload/fck_upfile/file/jusalibiwimalopamoros.pdfIn PDF document text
    • http://nurugelexport.com/ckfinder/userfiles/files/51944670536.pdfIn PDF document text
    • https://rajatotogroup2.com/contents/files/8150658924.pdfIn PDF document text
    • https://yenicekentkaplicasi.com/userfiles/file/21242326796.pdfIn PDF document text
    • http://ovartec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613413e15144e---3175597135.pdfIn PDF document text
    • https://aparcaderoshaddaichile.cl/uploads/images/files/58660706114.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/59153477834.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/r5en7uul1fd646pa84s94eieg7/767264940.pdfIn PDF document text
    • https://successalpha.team/upload/files/megipatagakewutugajido.pdfIn PDF document text
    • https://www.domaine-de-la-ferme.fr/ckfinder/userfiles/files/logewegikafese.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/79d48f42c79c7195fc30d2f835f7e2d9/lepidokis.pdfIn PDF document text
    • https://novinfasteners.com/userfiles/file/20618333112.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_off0000de73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE73 11104 bytes
SHA-256: 8a5abb61715d9f9a32f5a60777a2a9459f6232199c04583794e670f36b566e1e
font_01_sfnt_off0000f802.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF802 18160 bytes
SHA-256: a0c8890112d95941dc074020f1f218b27848ac6e46caf036bdec77d6def64df9
font_02_sfnt_off0001279a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1279A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1