Malicious PDF — malware analysis report

Static analysis result for SHA-256 999e76ed2e91aa23…

MALICIOUS

PDF

36.1 KB Created: 2020-10-18 16:53:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 06cb397c798bef5c22d2f0379c13a912 SHA-1: 6714c939bca73938c2e40e9cccdaedcff3af3ada SHA-256: 999e76ed2e91aa23771050061f807ce15a57eeb57c6ee50db546350036b74703
184 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting, and one specifically to a known malicious redirector. The document body, though heavily obfuscated, contains the text 'Descargar juego de ajedrez para pc' and the malicious URL, suggesting a lure to trick users into downloading potentially harmful content. The ML classifier strongly supports the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://cctraff.ru/strik?keyword=descargar+juego+de+ajedrez+para+pc In PDF document text
    • https://nulixedupalaz.weebly.com/uploads/1/3/0/7/130739510/lotunijiwapuxinu.pdfIn PDF document text
    • https://rezizeme.weebly.com/uploads/1/3/0/7/130775554/gekinafataluji.pdfIn PDF document text
    • https://bogadisosupotaj.weebly.com/uploads/1/3/0/7/130776541/f03c1182fc06f.pdfIn PDF document text
    • https://winomumamo.weebly.com/uploads/1/3/1/0/131070375/nebiremopokexukite.pdfIn PDF document text
    • https://jukafubu.weebly.com/uploads/1/3/0/8/130874261/kozusomotugug_kenuluxe_varuwitarimov_kuvixemas.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365547/normal_5f8954f596bc7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375070/normal_5f8aee951b91d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365551/normal_5f8b4c55aa4fa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366017/normal_5f872bd06a59d.pdfIn PDF document text
    • https://juragubiv.weebly.com/uploads/1/3/0/8/130874328/0047b7cfd0.pdfIn PDF document text
    • https://riwisasivituw.weebly.com/uploads/1/3/1/0/131070703/7337237e7b527c.pdfIn PDF document text
    • https://voxapinave.weebly.com/uploads/1/3/2/7/132740917/6f145.pdfIn PDF document text
    • https://kukotefuses.weebly.com/uploads/1/3/1/6/131637352/ec8752b2c222.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367281/normal_5f87507b49d6f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373259/normal_5f8a4164e8ac1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/7245/4810/files/78171097887.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0495/5255/6184/files/tilozidusuxobe.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0483/0376/7715/files/lupikonegix.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/de8bc2a4-e601-4abd-b453-6f5f3ad8fc7e/gumefojimifepipatul.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2057b6d0-6554-4554-8896-d7feaca7b244/engineering_mechanics_statics_5th_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/73a5c3f7-b734-4bb0-9403-23b6f53fa60b/58950890537.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/daf28e0d-82a0-420b-82dd-01775bf8c231/sijupeba.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_off00004f9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4F9F 5332 bytes
SHA-256: 286bb6c10f746fe7a6af1f0d42e1911befb303b566ca29c571a5220976685a57
font_01_sfnt_off000061dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x61DC 9772 bytes
SHA-256: 3dac970be3a665db5293faac1a220d17f7a7587f5d059489218653901c5914d7