Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6ecfb95845f8b11…

MALICIOUS

PDF

74.7 KB Created: 2021-03-09 07:54:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 101dfe808871952ca3b05a65b6aba07e SHA-1: 9456fc121a1166f514b71ffc71edf0189df0ae22 SHA-256: f6ecfb95845f8b11934b6dba3ecb4bb716ac21dbe8ddebfec65e6d5845991360
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to PDF files hosted on subdomains of cdn.sqhk.co, suggesting a link farm or redirection mechanism. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as phishing. The document body, though heavily obfuscated, contains keywords related to medical search terms, likely used as a lure to attract users to the malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://golowaki.ru/award?keyword=arteria+uterina+doppler+pdf PDF link annotation
    • https://cdn.sqhk.co/rubalibuzodi/tukTFjf/dixew.pdfIn PDF document text
    • https://cdn.sqhk.co/duzoxibuf/p34Igib/personal_fitness_training_certification_online.pdfIn PDF document text
    • https://cdn.sqhk.co/kufagilan/gjiHFm1/wajaneg.pdfIn PDF document text
    • https://fejejupusojovif.weebly.com/uploads/1/3/1/4/131483068/kupoworad.pdfIn PDF document text
    • https://cdn.sqhk.co/tupulezi/iVFD0yw/kejawid.pdfIn PDF document text
    • https://cdn.sqhk.co/defalevoruw/ckkjeib/defense_zone_3_hd_unlimited_money_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/tinulafi/jg2hegg/pof_dating_site_plenty_of_fish_sign_in.pdfIn PDF document text
    • https://cdn.sqhk.co/vawapisoxe/7EhgRgd/jeep_gladiator_3d_model.pdfIn PDF document text
    • https://cdn.sqhk.co/nigulavax/jhyibjb/7433818162.pdfIn PDF document text
    • https://kijujula.weebly.com/uploads/1/3/4/7/134756294/gowazevevetak-xogagigowazofes.pdfIn PDF document text
    • https://cdn.sqhk.co/raxipopu/gi6YAKV/just_dance_2020_controller_android.pdfIn PDF document text
    • https://linajijokib.weebly.com/uploads/1/3/4/0/134000065/7544815.pdfIn PDF document text
    • https://cdn.sqhk.co/kisasizaro/8O6he9n/jutifamitam.pdfIn PDF document text
    • https://cdn.sqhk.co/vovigewuva/5hcBt3c/big_business_from_my_dream_house.pdfIn PDF document text
    • https://felomogolupa.weebly.com/uploads/1/3/4/3/134345494/leserojikir-viwofilopebus.pdfIn PDF document text
    • https://cdn.sqhk.co/kolusugego/ROl6jdQ/phoenix_zoo_lights_halloween.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd4b4ca0-97d5-427d-ab90-e4c726d23fe3/que_indica_el_monitor_de_signos_vitales.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/159660e3-cf7b-4b16-b69e-dc6c585cc02e/what_size_battery_for_baby_swing.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e57f1326-d562-4f01-b653-64721b3bbdbd/zelonifoguguwutenu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb244dc8-73db-4d24-9b03-a80a58208f80/85418454588.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6df9172-7875-453f-8c3c-f0516b337e5e/printable_book_report_template_5th_grade.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9c664fa-c176-4d29-82a0-189587383c81/how_to_install_a_ao_smith_heat_pump_water_heater.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8065c5e7-1aa1-4d7d-b687-482db92d6aa6/kavezeduwawomu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9c09e69-f594-466f-98c7-2e3b128b1698/maserati_granturismo_sport_mc_stradale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b1477ee-5131-4014-bc27-ec5766fb262d/afterlife_lyrics_future.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_off0000e982.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE982 4848 bytes
SHA-256: 3d1f2b64eb49cccc97b2d95eb0b9e2c06b23dbdb17b66eb5fa2c6c9b8c12f718
font_01_sfnt_off0000fa0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA0F 10328 bytes
SHA-256: 3b9d183b8d86303ce152493ee21547c1de9d612e02203ee60fa86debdf6cf734