Malicious PDF — malware analysis report

Static analysis result for SHA-256 13c937ef9905dedf…

MALICIOUS

PDF

76.3 KB Created: 2021-03-08 23:15:29 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-04
MD5: 6dde553344608bf7c4af983b6cda61a1 SHA-1: cb531e241c4d307f21b8c47b8277218c2538940f SHA-256: 13c937ef9905dedfc17e16b984c12df3fbfafa04cee4b1dd9703838e9b1bb673
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, suggesting a phishing or malware distribution attempt. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such domains for malicious purposes. No scripts were extracted, but the PDF structure itself is designed to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://golowaki.ru/award?keyword=aoac+methods+pdf+volume+2 PDF link annotation
    • http://lajodibibodi.getenjoyment.net/children_of_dune_imdb.pdfIn PDF document text
    • http://nout-prokat.website/business_proposal_sample_powerpoint_presentationxnkss.pdfIn PDF document text
    • http://mandarins.space/fonuroxon1s36d.pdfIn PDF document text
    • http://bestrongbyg.com/fafuwexinexozahvk3.pdfIn PDF document text
    • http://missunik.space/whatsapp_status_video_iphonerx2vl.pdfIn PDF document text
    • http://jakesubinosol.scienceontheweb.net/qu_es_una_fotografa_area.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/1e64295f-a9fa-41a5-9e8b-178dcb246fce/sharp_roku_tv_32_inch_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/daac923d-fa68-4d6e-b9de-3ec526e4c071/flight_sim_x_helicopter_controls.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a1db3f4-1fd9-4a68-85a1-eef6eef8df10/fantastic_mr_fox_quotes_wolf.pdfIn PDF document text
    • http://duxegejuw.atwebpages.com/puxigozogeridegonomipaw.pdfIn PDF document text
    • http://vejegaba.atwebpages.com/puzaxikeraze.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be0423f2-a087-4bef-a88f-10b154b3a1c4/narrative_of_the_life_of_frederick_douglass_summary.pdfIn PDF document text
    • http://zupitatip.atwebpages.com/61502635617.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8798fbaf-151b-46dd-b14c-c011a58f58eb/excel_vba_input_box_with_options.pdfIn PDF document text
    • https://s3.amazonaws.com/rumezo/calendario_civico_escolar_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4f30448-7373-4322-94ec-3c07f3858590/what_does_horizontal_force_mean.pdfIn PDF document text
    • https://s3.amazonaws.com/xuxifuzituwu/vatudalajenagun.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5959a1b3-ff34-4744-bc52-9ab8547a613e/harry_potter_book_1_chapter_8.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1688f84e-6e0b-4640-ae4c-1831e627e34a/imagenes_de_la_boda_de_eva_luna_montaner_y_camilo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab559591-1bd3-4df1-9553-08967c70e7bd/femerofirurav.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b54e4171-1072-4430-9ec7-eb9dd3495c9f/nonejosadezuwop.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f64466ee-98cc-4fa7-9b7b-1d81e602cc0b/91751779073.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55538f04-206c-48a4-bb31-27ccff4cd2e4/sample_spm_english_paper_1_directed_writing.pdfIn PDF document text
    • https://s3.amazonaws.com/nimuwet/42704264062.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_off0000ee3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3D 5480 bytes
SHA-256: f1f0008b62566fef795d644f4b7596ea43199ad167c5390f15da5e0480a34b3b
font_01_sfnt_off000100cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100CB 10064 bytes
SHA-256: f4450a1b37faa2278f3bca15edf1528299eae2365b5b7a63e1bd5449613673d2