Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4cfe056306e94e3…

MALICIOUS

PDF

81.3 KB Created: 2021-05-28 22:07:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 69c3ddc6b59acf524a03484ba5d49ee3 SHA-1: 74786d73605216bd7bc9f238f6824626464d24bd SHA-256: c4cfe056306e94e3f9250894630a10f30fb27cc1f2fd4259af4b3820a0019d10
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nipisod.ru/strik?utm_term=reading+comprehension+worksheets+8th+grade+multiple+choice PDF link annotation
    • https://giminefimir.weebly.com/uploads/1/3/0/9/130969553/863224.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367944/normal_60407c003024a.pdfIn PDF document text
    • https://moremutinujiti.weebly.com/uploads/1/3/4/8/134865562/jukegekefijilebav.pdfIn PDF document text
    • https://munemajof.weebly.com/uploads/1/3/2/3/132302982/fezironurawugaduja.pdfIn PDF document text
    • https://bijariruxo.weebly.com/uploads/1/3/1/3/131382387/8d135ea0f.pdfIn PDF document text
    • https://nasoxatexiwek.weebly.com/uploads/1/3/0/7/130739087/4248262.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459034/normal_60361f616cea3.pdfIn PDF document text
    • https://wojewifonutej.weebly.com/uploads/1/3/4/8/134883442/33c96.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/2d65cf67-b1c3-41b6-a8ba-ddf9b4ec73fa/python_gui_programming_using_tkinter.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55e4b568-5e3e-4154-aa2c-d78c2140a8a3/how_to_adjust_straps_snugride_30.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d77bd67-cf91-404d-b3d3-7d1fc327d245/wolufedadex.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9cf88a49-012c-4c68-96e0-1156861d11d9/injustice_gods_among_us_mod_apk_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be36b1aa-fec1-4e6c-870f-0a06f5a4ebae/how_to_check_if_your_certified_mail_was_delivered.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/46ff99dd-7dea-4141-9992-88b022402236/27880059463.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20b1a0da-4789-4317-98ee-5d02e61e0335/purixakara.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b599aee2-e945-459a-bc32-3b9d6c8be836/puwegivi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/642d75e4-9351-4ffb-a7ea-61d71d067408/rasibuju.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0898a91e-1d67-4769-95ef-afb2de8f2126/maxi_cosi_pria_70_car_seat_travel_bag.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c7aa840b-1e17-467a-b3d7-cca1181bcc0d/suwazutezigujoluw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e5082c4-d864-4d9e-a546-132df7b6aaad/75478728494.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_off0000fdd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD1 5844 bytes
SHA-256: 48c93d0a3828c9b24ea47724c084410bc430fc8337e5615dea49f12e21368ac2
font_01_sfnt_off000111a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111A3 11216 bytes
SHA-256: 734f974679cb46b7d5f27a03eb895b0a55773312125199f408c3bfec3e604964