Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c7d67eb31aaef19…

MALICIOUS

PDF

105.1 KB Created: 2021-05-01 20:12:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 65768ad8e7f40f70633852b56c624ff1 SHA-1: d40e41f819955cf6113e31e7cfaf3d741974561e SHA-256: 4c7d67eb31aaef19ddf481bc8a858a10ec254a19273b0179b558af91af78dc7e
244 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, many pointing to external PDF files hosted on disposable domains or link farms. One critical heuristic identified a link to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://crophysi.ru/strik?utm_term=why+were+the+members+of+the+third+estate+dissatisfied+with+the+old+regime In PDF document text
    • https://cdn-cms.f-static.net/uploads/4457332/normal_6064842d31402.pdfIn PDF document text
    • https://tirotulesi.weebly.com/uploads/1/3/4/8/134849952/tilakenawunefe.pdfIn PDF document text
    • https://cdn.sqhk.co/bugolajoxodu/gjaifr8/free_stuff_usa.pdfIn PDF document text
    • https://xonatiwomunonow.weebly.com/uploads/1/3/1/8/131856992/kozeto_fotazaribi_relapu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450046/normal_6057e8d8339f6.pdfIn PDF document text
    • https://cdn.sqhk.co/dudilirugido/gjfjghh/duck_life_space_full_game_unblocked.pdfIn PDF document text
    • https://lujukote.weebly.com/uploads/1/3/2/7/132712447/dupivote.pdfIn PDF document text
    • https://bonopabugo.weebly.com/uploads/1/3/4/5/134581776/9512078.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4503874/normal_601914f5e1386.pdfIn PDF document text
    • https://cdn.sqhk.co/sovokeduseb/WJl9BmZ/88204709159.pdfIn PDF document text
    • https://netigobulon.weebly.com/uploads/1/3/4/0/134096742/digegiragituj-rodoputenabake-dipaledox.pdfIn PDF document text
    • http://kufadudaz.iblogger.org/rotamon.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483083/normal_5fddc565d70ec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366665/normal_601755b1e70cb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463543/normal_60383272b33d8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393635/normal_603370aa916da.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://punugituk.epizy.com/araria_map.pdfIn PDF document text
    • http://kufitaxasatuze.rf.gd/bissell_proheat_2x_revolution_pet_brushes_not_spinning.pdfIn PDF document text
    • http://rilifufamorupud.epizy.com/dozawavisavula.pdfIn PDF document text
    • http://pekuvem.epizy.com/basketball_game_score_sheet.pdfIn PDF document text
    • http://tizepadeda.rf.gd/er_app_apk_for_firestick.pdfIn PDF document text
    • http://lafasusatar.rf.gd/31135759124.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_off000156c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156C6 5668 bytes
SHA-256: fa48d7307490f215d885a9f129b6a3035ea741c7887b857b014fc44126a69bee
font_01_sfnt_off00016a04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16A04 13412 bytes
SHA-256: 8487f1eb381fdfeb0060a8d9c96b1c994a2cc24ed2d9ee54747412e86a648977