Malicious PDF — malware analysis report

Static analysis result for SHA-256 51760c35f9ab2606…

MALICIOUS

PDF

97.8 KB Created: 2021-03-25 08:05:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 23b3ff7a664181f7f000af39de4691c4 SHA-1: 22d7bbd956400a71f329e2528d7ded5ecf3450bb SHA-256: 51760c35f9ab2606c25439c47e724d4b19af89fef29559a5d7f9ba176c19e86b
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links hosted on disposable domains, a common tactic for phishing and malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest it's designed to lure users to malicious sites, potentially for credential harvesting or further payload delivery.

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
  • 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://xezojetit.ru/123?utm_term=coryphantha+pycnacantha+cacti+guide PDF link annotation
    • http://health2health.online/how_to_write_a_poetry_book_in_wordy4l4m.pdfIn PDF document text
    • http://digogipexoluku.iblogger.org/4354085015.pdfIn PDF document text
    • http://m-ryanaf.site/exercices_comparatif_superlatif_en_anglaisfdi3a.pdfIn PDF document text
    • http://fastcreditcheck.info/73950537778xpz1y.pdfIn PDF document text
    • http://alisaborodaenko.design/adhd_diagnosis_uk_nice_guidelines1zjvy.pdfIn PDF document text
    • http://ekzo-fruit.ru/cradle_to_cradle_chapter_4_summaryaorld.pdfIn PDF document text
    • http://shopbest.online/lapetofukemexokegaliwemp0372.pdfIn PDF document text
    • http://copyrightshelpscenters.com/60753266811zlfgq.pdfIn PDF document text
    • http://organize.shop/wardrobe_furniture_design7zybk.pdfIn PDF document text
    • http://wutugavefezaza.22web.org/descargar_plan_y_programas_de_estudio_2011_cuarto_grado.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/dc044f30-0c67-4ff9-a09e-345a28e7efe7/the_dream_of_the_rood_analysis.pdfIn PDF document text
    • https://75a697d3-84f0-44cf-bab9-f05e37020c50.filesusr.com/ugd/7c3584_e7cafa4b452a4691b55e1d93acead034.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0e33a005-60d7-4dc1-9deb-35c78d672c3e/pixilowiwiri.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb7aea2d-5d6e-4924-8ffc-c38cac654b4b/what_is_the_power_of_one_horse.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/00d427a5-59c6-4dd4-9b7b-ee49de891d0b/how_to_connect_hp_deskjet_3050a_to_wireless.pdfIn PDF document text
    • https://8d2868a3-57b7-484c-81f6-493c1c4f5daa.filesusr.com/ugd/a8ca0f_5c9e7256e0704a608d02fb02495fd1ae.pdf?index=trueIn PDF document text
    • https://9ebe8999-295a-4f11-87dc-c96f3e1b46ff.filesusr.com/ugd/8de238_367880d3abf44e05bcd4d0a0840834a4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1dc1bf00-ef86-46db-a6b4-ae7d391b4286/what_age_draw_a_face.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eddcc3ea-2ad9-4db5-8b37-0032126411a9/scl-90-r_scoring.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b2313fe1-97fd-4fd9-b3fd-9186180631dd/50193914728.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/841ce13e-8a6f-4729-9093-f72e66081af1/convert_pic_to_black_and_white_in_paint.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_off00014453.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14453 5132 bytes
SHA-256: 1f5d55a86189982df1c1bad98e888371b35faedc33f4dc9f54c21e8eb65f2a2f
font_01_sfnt_off000155c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x155C4 10692 bytes
SHA-256: 883c3eb416279adeef6c535934ad806d513218fc8a4baa933761826187a208ea