Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac71f621bd2ee983…

MALICIOUS

PDF

80.5 KB Created: 2021-04-03 08:34:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 8d96365b755161f71a8a47d2e5b0443a SHA-1: db74b582db1493b948254edb9662b4797e57600d SHA-256: ac71f621bd2ee9832d64921328326b63231f3fac5f89b352267979e5b3fefea6
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs, with a primary suspicious URL being `https://resalured.ru/award?keyword=las+asignaturas+en+ingles+ejercicios+pdf`, which is presented as a search result to trick users. The heuristic `PDF_SEO_DISPOSABLE_LINK_FARM` further suggests a malicious intent to distribute links across disposable hosting. No scripts were extracted, but the overall structure and URL distribution point to a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://resalured.ru/award?keyword=las+asignaturas+en+ingles+ejercicios+pdf PDF link annotation
    • https://s3.amazonaws.com/pajukovuxetu/whirlpool_built_in_microwave_manual.pdfIn PDF document text
    • http://cafe-cok.ru/57686478656pj0bm.pdfIn PDF document text
    • http://rent-nout.site/2007_jeep_grand_cherokee_starter_solenoid_wirea2wqe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457008/normal_5fce0727b03be.pdfIn PDF document text
    • http://1yamal.space/38089706612vgjex.pdfIn PDF document text
    • http://richmaya.site/yamaha_rx-v377_specse4kgc.pdfIn PDF document text
    • https://s3.amazonaws.com/nefunupu/kekekafekudinabib.pdfIn PDF document text
    • http://moviesaddaa.online/water_parks_in_paris_franceh2c4w.pdfIn PDF document text
    • http://normal-id.com/shadow_sae_niijima_boss_guidewbqqr.pdfIn PDF document text
    • http://dipenoguzel.sportsontheweb.net/75188168240.pdfIn PDF document text
    • http://vsedlyatebya.xyz/vivanoguziwadozegoocgb4.pdfIn PDF document text
    • http://napowojeba.medianewsonline.com/98882583402.pdfIn PDF document text
    • https://s3.amazonaws.com/xidazeze/95111330260.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4497075/normal_5fcd96290d0a1.pdfIn PDF document text
    • https://s3.amazonaws.com/kegubinefuda/61435458082.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466165/normal_604fcb262d3df.pdfIn PDF document text
    • https://s3.amazonaws.com/pezofut/oro_solido_el_beeper_song.pdfIn PDF document text
    • http://wonder-ita.space/49064073477ydj24.pdfIn PDF document text
    • http://kalavar.xyz/free_video_er_for_iphone_6_plusomi22.pdfIn PDF document text
    • http://milansit.space/the_bible_the_quran_and_science_book_in_urduz9fzo.pdfIn PDF document text
    • http://groshyk.site/boy_scout_merit_badge_sash_sizelcwi6.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://bixozebaxikapos.atwebpages.com/kinetics_of_condensation_polymerization.pdfIn PDF document text
    • http://zibelasavu.atwebpages.com/sirozuv.pdfIn PDF document text
    • http://makakanow.onlinewebshop.net/how_to_pair_a_plantronics_voyager.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_off0000fa1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA1D 5340 bytes
SHA-256: 67035b08ce953e1dcbd98e291b748c41cd757b8b44e0c83200712ff3c264def4
font_01_sfnt_off00010c5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C5E 11744 bytes
SHA-256: cf1a1c9e978b5047b70528d9e2ff86f2cd38de9d6b4eae5c70f7dd5d5bbc77eb