Malicious PDF — malware analysis report

Static analysis result for SHA-256 6da7364add79bf3f…

MALICIOUS

PDF

82.9 KB Created: 2021-04-02 08:02:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 05c83ba96f745f5046df517603adafe8 SHA-1: 2b482ab9dd80319f463175bd1063dd2de787e7aa SHA-256: 6da7364add79bf3fe3650f504620e85deca56ca9a178651a51ba72c92bdd3123
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan distribution attempt. The heuristics reveal it contains a large farm of external links, many hosted on disposable domains, designed to redirect users to potentially malicious content. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create SEO-spam PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • 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 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://xajibur.ru/123?utm_term=bioassay+pdf+slideshare PDF link annotation
    • https://cdn.sqhk.co/bekutojeke/thgiahd/bozugerepumijiw.pdfIn PDF document text
    • http://tezoxefakalexo.sportsontheweb.net/72952589600.pdfIn PDF document text
    • http://febiterozoz.medianewsonline.com/86130202761.pdfIn PDF document text
    • https://cdn.sqhk.co/zolewiko/TnC9Tha/free_simple_loan_agreement_template_australia.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450037/normal_60544addefe3e.pdfIn PDF document text
    • https://cdn.sqhk.co/wixakulu/hgjdhbg/haunted_tunnel_car_wash_huntington_beach.pdfIn PDF document text
    • https://cdn.sqhk.co/panajevem/geTsQaV/snes9x_ex_android.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450878/normal_604d89ec69c77.pdfIn PDF document text
    • http://lunatan.medianewsonline.com/34199051001.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456378/normal_605f5c63b267b.pdfIn PDF document text
    • http://gunofixe.medianewsonline.com/across_the_bridge_free_download.pdfIn PDF document text
    • https://cdn.sqhk.co/vinikawikuve/idhjNgh/awd_turbo_cars_under_15k.pdfIn PDF document text
    • https://cdn.sqhk.co/jakufomego/hbNpEhd/ririxavolurexafupuwivow.pdfIn PDF document text
    • https://cdn.sqhk.co/gosukutusu/hKgdjiU/17723012996.pdfIn PDF document text
    • https://cdn.sqhk.co/kixowijeka/Yhbifjf/zulevusiduxip.pdfIn PDF document text
    • https://cdn.sqhk.co/vukupamita/ijXigpT/nugujilipos.pdfIn PDF document text
    • https://cdn.sqhk.co/votezevon/cheksey/nuzobitamixumo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451941/normal_6039c6f48e80c.pdfIn PDF document text
    • http://fontawesome.iohttp://fontawesome.io/license/In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://c18d9829-3add-4afa-bc87-35007fe3998a.filesusr.com/ugd/70c1ec_a986ea027a6b46acb2d580682147985b.pdf?index=trueIn PDF document text
    • https://435a888a-8f80-410d-aa77-77edd6e4491d.filesusr.com/ugd/51fec0_5af4908480c14d70b60bb2403206ed12.pdf?index=trueIn PDF document text
    • https://27aa3d6a-fcc1-4574-a8e0-77dd5bf64dcc.filesusr.com/ugd/7683ec_4b1bd02848314dc98fd065ea0c6b9e26.pdf?index=trueIn PDF document text
    • https://c301b42c-deab-4116-afcd-a09dd0728425.filesusr.com/ugd/4bb894_a462fd7b94284b3a95398beea8dc0626.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fc2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC2C 1888 bytes
SHA-256: 3ad05f93d08dde6e4c8a5553019f130d4d27074cfb443b77530fd8f2df49c570
font_01_sfnt_off00010518.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10518 5280 bytes
SHA-256: ddb8b0a5ea366cab85abc6ae46c4966f8d988cdfc2c7077181a623ca3960afa5
font_02_sfnt_off0001170d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1170D 11388 bytes
SHA-256: e3bd45f504bd779df416f2a23d7df3b63e6256721cfb5e684e9efc0a148b193f