Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a7e04714908c0d0…

MALICIOUS

PDF

72.0 KB Created: 2021-04-20 14:16:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: faf8b0aa77c63e9b6e4441ebfbe660e4 SHA-1: 0ba089fc6484a705d76a6ee6252fa5b9fbd18b97 SHA-256: 4a7e04714908c0d0e11f498d207e0866f342e3bcc68e2f6e7dd2fce183dc11a2
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, with a significant number pointing to disposable hosting, indicative of a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://zajinet.ru/strik?utm_term=denon+avr-x4100w+manual PDF link annotation
    • http://kipokefurur.mygamesonline.org/aleister_crowley_libros_espaol.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382430/normal_604aeacb9b0dd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4444850/normal_6008afd957dec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460461/normal_60344ed303e0d.pdfIn PDF document text
    • https://tufemetu.weebly.com/uploads/1/3/4/8/134887907/guxumazudevurosiduf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449014/normal_605d794042729.pdfIn PDF document text
    • https://sebikiwar.weebly.com/uploads/1/3/5/9/135962157/6208259.pdfIn PDF document text
    • http://gagapazu.scienceontheweb.net/nace_cathodic_protection_handbook.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460251/normal_60654f36222b6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4468255/normal_5fccb9b63d8cc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451744/normal_5fdfa538b933b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488570/normal_5ff24d8ec4bb2.pdfIn PDF document text
    • http://laludinemolat.sportsontheweb.net/anatomie_du_corps_humaine.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462059/normal_5fe6b5dddeda1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://telosizaba.onlinewebshop.net/carnatic_music_keyboard_notes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0de8baef-ead4-4d82-98e6-b6eaa9120bdc/safuler.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4346034e-a80b-4452-89fc-979efc514572/ping_pong_websocket_javascript.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bf43f6e9-1b93-41e2-8668-a39a8561a737/xikenagipakuboxoxofi.pdfIn PDF document text
    • http://jugomirusulove.atwebpages.com/23311394359.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d756.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD756 5184 bytes
SHA-256: ffbac3d2e011afb90717be3db75a324b512f857881dccc0323cca509014df5d6
font_01_sfnt_off0000e910.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE910 12612 bytes
SHA-256: da70a6583af0393884b09559cd9af5426f3cf059737f9a4fedcec241a427fa7d