Malicious PDF — malware analysis report

Static analysis result for SHA-256 b755fbc5ca40530d…

MALICIOUS

PDF

70.1 KB Created: 2021-03-09 06:31:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 236a4b637f0c1e4b57d4cff533c6cce7 SHA-1: c1fb8d881b4711f125a6233a7a4fac5a068a6647 SHA-256: b755fbc5ca40530d0f1fc6921026d8f0ec78ad9138bbe635aaff29cd579d585f
244 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm designed to redirect users to potentially harmful sites. The presence of a link to `https://yafferge.ru/123?utm_term=block+breaker+apk+mod` strongly suggests a phishing or malware distribution attempt. The document body is heavily obfuscated and unreadable, preventing further analysis of its specific content or intent beyond the detected link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/123?utm_term=block+breaker+apk+mod In PDF document text
    • http://terugate.mypressonline.com/kosivawitakowofib.pdfIn PDF document text
    • http://vodoroding.info/what_is_the_7_x_tablekxrwg.pdfIn PDF document text
    • http://lnstagram-helping.live/why_is_kingkiller_chronicle_so_popularotr3x.pdfIn PDF document text
    • http://bibivire.mygamesonline.org/what_car_seats_are_compatible_with_graco_ready2grow_stroller.pdfIn PDF document text
    • https://cdn.sqhk.co/dudugetogi/fhdhcVT/pokimane_boyfriend_bjergsen.pdfIn PDF document text
    • http://ketaton.mywebcommunity.org/avalon_astoria_pellet_stove_troubleshooting.pdfIn PDF document text
    • https://cdn.sqhk.co/lamiwifa/cgjQjja/52893614086.pdfIn PDF document text
    • https://cdn.sqhk.co/kinibemazoz/fjGAgcd/qa_automation_engineer_resume.pdfIn PDF document text
    • http://navaram.online/753061580319u55m.pdfIn PDF document text
    • http://bitiwiz.medianewsonline.com/52636921459.pdfIn PDF document text
    • https://cdn.sqhk.co/ruwonumatag/dz6hf6y/46041621541.pdfIn PDF document text
    • http://fajutixosisi.22web.org/ps4_bruteforce_save_data.pdfIn PDF document text
    • http://sellforce.ru/black_friday_iphone_deals_2019_uk_apple9fxap.pdfIn PDF document text
    • http://usesalle.xyz/runutelodepajefaxegarr6kzp.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8b8c7005-3af0-45a1-8e5b-a6902caa9335.filesusr.com/ugd/dbd7d9_09bd91f47a0246cc8e4e7d048cf8974b.pdf?index=trueIn PDF document text
    • https://044ec7df-721b-4788-b209-87474a3fcb06.filesusr.com/ugd/60ffa2_8d92b43d05a945eb85795367dfc48213.pdf?index=trueIn PDF document text
    • https://9ef77391-fdd1-48d8-ba15-364b07375333.filesusr.com/ugd/ebefdf_4e7b493cd6a04a39a2bc1c41d3756fde.pdf?index=trueIn PDF document text
    • https://7f58a6d3-5723-489e-a2bd-17fd91e1ddd5.filesusr.com/ugd/655495_31e0ef35e1844b1ca39c2d445ae43ad1.pdf?index=trueIn PDF document text
    • https://807eaacf-9fb6-4e16-bcb8-061395d1d132.filesusr.com/ugd/a3ef2e_5e73cca29f814484bbe8f1128b71d634.pdf?index=trueIn PDF document text
    • https://507d1b22-ea03-4061-a262-f79425337ca2.filesusr.com/ugd/a374b9_0f14877014af4e22b7c0bf523ac4da7d.pdf?index=trueIn PDF document text
    • https://f9c81679-ddb1-4746-ab40-32673edc426c.filesusr.com/ugd/2eff39_056cf882f4f4464d9cd4cdcacf609ae2.pdf?index=trueIn PDF document text
    • http://volomuladifute.rf.gd/allamuchy_weather_report.pdfIn PDF document text
    • http://ledukuxadom.epizy.com/takupapekurubuvura.pdfIn PDF document text
    • http://damaxokabipo.epizy.com/sentencia_alsasua_supremo.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_off0000d43d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD43D 5292 bytes
SHA-256: 76424540531b451cb06bcefdfee04144cdb10c7856213585c848a4cd0dd945f7
font_01_sfnt_off0000e625.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE625 10952 bytes
SHA-256: 826f0d7ffd7d3f60ec8b0d72460f60c66d612f9b6f8aef8c35dd5141b617f421