Malicious PDF — malware analysis report

Static analysis result for SHA-256 f25851b7c19ac2e7…

MALICIOUS

PDF

132.5 KB Created: 2021-05-06 02:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 48860ba5016cfd523b60850d3ed6ec97 SHA-1: d6dd8ce80203d37fc51b3dc734dd2ecf4043b63d SHA-256: f25851b7c19ac2e769269d1a1d49f374a3b31612677dad36c80a973e2a5404f5
264 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many pointing to disposable hosting and redirectors, indicating a link farm designed to obscure malicious destinations. The document body, though heavily obfuscated, contains text related to 'dispute with sprint', aligning with the 'SE_CALLBACK_LURE' heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 7

  • 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 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://crophysi.ru/strik?utm_term=how+do+i+file+a+dispute+with+sprint In PDF document text
    • https://vigusukababimer.weebly.com/uploads/1/3/4/8/134881512/55b2de30d6d3fea.pdfIn PDF document text
    • http://lumejaramelu.mygamesonline.org/76474034979.pdfIn PDF document text
    • https://cdn.sqhk.co/fenazijeguk/PiegjWw/the_walking_dead_season_1_episode_2_game.pdfIn PDF document text
    • https://cdn.sqhk.co/wavagowew/jbiaji8/360848324.pdfIn PDF document text
    • https://dezijetide.weebly.com/uploads/1/3/4/8/134864221/vozifuvabexuko_sufataxujemom.pdfIn PDF document text
    • https://kaxojolomo.weebly.com/uploads/1/3/4/8/134885197/5026861.pdfIn PDF document text
    • https://kukixagunobi.weebly.com/uploads/1/3/5/3/135325453/3e317.pdfIn PDF document text
    • https://cdn.sqhk.co/pijavagoke/mjhjbif/stampede_meat_bedford_park_il.pdfIn PDF document text
    • https://gakefutafo.weebly.com/uploads/1/3/0/7/130739004/riwadovazabogufe.pdfIn PDF document text
    • https://cdn.sqhk.co/gujawovuk/hhFQ4z9/define_guided_tissue_regeneration.pdfIn PDF document text
    • https://tunegize.weebly.com/uploads/1/3/4/5/134500295/dalusokeb.pdfIn PDF document text
    • https://cdn.sqhk.co/gizoxemovefi/gsUgfgf/tonto_jump_on_it_fresh_prince.pdfIn PDF document text
    • https://xisezuvu.weebly.com/uploads/1/3/4/0/134096300/79c4ba229f332e.pdfIn PDF document text
    • https://cdn.sqhk.co/povewepalu/PcTgf5x/archery_equipment_for_sale_near_me.pdfIn PDF document text
    • http://xezixaz.getenjoyment.net/93251605930.pdfIn PDF document text
    • https://cdn.sqhk.co/naboxolat/eigjgQA/mesoxorubosokuvufa.pdfIn PDF document text
    • http://bakavorun.getenjoyment.net/11942162868.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://bugenerefajujus.atwebpages.com/16054228350.pdfIn PDF document text
    • https://6cda4dd4-8aac-43e7-8003-7c0eea9f7907.filesusr.com/ugd/34e26e_a5177b9b40e849f6938cb4cd669bfbc2.pdf?index=trueIn PDF document text
    • https://ce099f17-eb12-430b-a452-8d789b3ee5a8.filesusr.com/ugd/aef5b7_ec38955ad1a14d11862bd2c3b9a60633.pdf?index=trueIn PDF document text
    • https://8a6b9437-e7f2-49d7-8c24-351b272aa67a.filesusr.com/ugd/b18e4d_995314b3f1c24589ad27a75eab87a10c.pdf?index=trueIn PDF document text
    • https://3dcfbd4a-ef33-49dc-a04a-0aaf5307c30d.filesusr.com/ugd/b47706_d98f59d6b3d8402ca8fad661f921a50c.pdf?index=trueIn PDF document text
    • https://527ed197-5826-4432-9c89-449afa9d705e.filesusr.com/ugd/65ef70_047fb7b61726437695896d9ba32a2d96.pdf?index=trueIn 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
    • 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_off0001b562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B562 5180 bytes
SHA-256: 6609dcb820afe22e2a6ae23f9ec7f8228240fcfa4158455d9fdaa1862dd52a10
font_01_sfnt_off0001c710.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C710 11560 bytes
SHA-256: fade7a52d591e6dd4bea71278ccc1554e4f14c4631701b8aca8fb5885cc203b8
font_02_sfnt_off0001ee9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EE9C 16060 bytes
SHA-256: f60502fb507c904334c4e6f64201f20e056641c8e54386132246a428bdda64b8