Malicious PDF — malware analysis report

Static analysis result for SHA-256 ebd19bb309113a49…

MALICIOUS

PDF

73.7 KB Created: 2021-09-17 15:08:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6891a8248cac337b86941ecf9a1f8761 SHA-1: f6caf3ee444b7a885b2c95dd234ed575b89e1ea3 SHA-256: ebd19bb309113a4935cf549266539bd0524dd2ee557074517f386713e80d3ea5
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://chcial.ru/uplcv?utm_term=how+to+turn+a+video+into+a+mp3 PDF link annotation
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6c3311985---59494227866.pdfIn PDF document text
    • https://kheops-so.fr/ckfinder/userfiles/files/63524140263.pdfIn PDF document text
    • http://kabaretyimpresariat.pl/Upload/file/sadajipokomutu.pdfIn PDF document text
    • http://ruresept.ru/files/file/48887404306.pdfIn PDF document text
    • http://synfarm.com/upload/files/39000126308.pdfIn PDF document text
    • http://homokkepek.hu/editor_up/nipexobijirubepefotu.pdfIn PDF document text
    • https://bak.vn/upload/files/dijefuxiwukud.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c18ff3594f---10176140215.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/6ff8ebd252b2b54709071fc66afc796d/52937183685.pdfIn PDF document text
    • https://gamepinleri.com/calisma2/files/uploads/19364452297.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/84332680086.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3e6cd42e8---45790413977.pdfIn PDF document text
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bb18c0ce09---sijuxipufugu.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/kedomof.pdfIn PDF document text
    • https://frigosztufi.ro/ckfinder/userfiles/files/99796394921.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/dc0ce59188ea24460b0ff3d54dc3b810/87565753644.pdfIn PDF document text
    • https://nirkongrp.com/ckfinder/userfiles/files/nodazurebamevewubof.pdfIn PDF document text
    • https://smg.bid/ckfinder_userfiles/files/wusenofozufoladarulawav.pdfIn PDF document text
    • http://themadthinker.com/temp/vinney/HTML/userfiles/file/buruledikimexali.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f054d98302---pofiwulovowiduvezaza.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_off0000bbb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d3c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3C3 17236 bytes
SHA-256: 92966d24239a4241db55233a2f60fee4ba6e4e5e6d2c88d515fad38da71a8314
font_02_sfnt_off00010082.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10082 10752 bytes
SHA-256: c327e9e301fa0b20a22665e813ad8a4bffd8c30205fbccaa37d6f8857ddb8a66