Malicious PDF — malware analysis report

Static analysis result for SHA-256 81158cf346c342bf…

MALICIOUS

PDF

93.5 KB Created: 2021-03-16 09:18:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 39e78a4bdccb4eb8f780c30298fc00e9 SHA-1: 522c99754df25786b04c9af384a3332b1b02ba5a SHA-256: 81158cf346c342bf669fc0367a61bfbb5e2040d7b39224db1bcace46554809f1
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to disposable domains, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious document designed to trick users into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://kuzutuzo.ru/wix?keyword=the+grim+grotto+pdf+free+download PDF link annotation
    • https://cdn.sqhk.co/nonuripot/rhcsZkQ/smashy_road_2.pdfIn PDF document text
    • http://sujabupinoda.scienceontheweb.net/read_autobiography_of_a_yogi_online.pdfIn PDF document text
    • https://dogamoduxex.weebly.com/uploads/1/3/4/4/134481485/rifozemewerawep.pdfIn PDF document text
    • http://fekevopimibun.sportsontheweb.net/charlie_and_the_chocolate_factory_music_original.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4423166/normal_5fcc541e7852e.pdfIn PDF document text
    • https://redobikarus.weebly.com/uploads/1/3/5/3/135396910/abc23852.pdfIn PDF document text
    • http://resokipuga.getenjoyment.net/madwoman_in_the_attic_jane_eyre.pdfIn PDF document text
    • http://rimiripa.mypressonline.com/browser_open_in_window.pdfIn PDF document text
    • http://mavigawika.scienceontheweb.net/bisas.pdfIn PDF document text
    • http://rabizepafuxonag.mypressonline.com/82945344069.pdfIn PDF document text
    • https://cdn.sqhk.co/fulaxanew/jgeQmOH/10392873401.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391907/normal_6003f06c863cf.pdfIn PDF document text
    • https://nitejaxerovon.weebly.com/uploads/1/3/1/3/131379530/zapepekenetugu_zomilazojokaf_miteberokijugus_matopepel.pdfIn PDF document text
    • http://linodogeb.scienceontheweb.net/brahmagupta_theorem.pdfIn PDF document text
    • https://cdn.sqhk.co/wowixepis/iuP7NMJ/vumawonewezi.pdfIn PDF document text
    • https://tuvopezape.weebly.com/uploads/1/3/4/7/134712323/b6436.pdfIn PDF document text
    • https://cdn.sqhk.co/sopiloroda/gHjcgeg/public_school_basketball_courts_near_me.pdfIn PDF document text
    • https://gadonivoxe.weebly.com/uploads/1/3/5/3/135331758/415333.pdfIn PDF document text
    • https://cdn.sqhk.co/nuzinirumawe/cchaeij/baby_alive_doll_boy.pdfIn PDF document text
    • http://ritegifufefut.scienceontheweb.net/luzijezasopuwuviberitunuw.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4427268/normal_5fcb0df171be5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/kujesulad/12295207932.pdfIn PDF document text
    • https://s3.amazonaws.com/bulolimepol/what_color_absorbs_more_light.pdfIn PDF document text
    • http://sanojepenot.onlinewebshop.net/aula_de_violo_para_iniciantes_gospel.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011947.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11947 4512 bytes
SHA-256: 22ded5b9f0eb3e420e24f3416c943baf6805d406429278c371bde73aa20fd016
font_01_sfnt_off0001292d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1292D 5320 bytes
SHA-256: 2d16f778d608df25fa9e9a7eb9694cb50d960d1a54b9fa571225a81c63597230
font_02_sfnt_off00013b2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B2E 14316 bytes
SHA-256: d29a69b0efe86a5edd0721c19a976449e1d6b22d95a12a556768e2804301cbd0