Malicious PDF — malware analysis report

Static analysis result for SHA-256 25497a17ec3db2fc…

MALICIOUS

PDF

70.3 KB Created: 2021-03-17 06:28:35 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 2802ab50a1eefde9b95e97d0a9e98a38 SHA-1: 3dc5409306028c10fe8af002ce2e4faa36323700 SHA-256: 25497a17ec3db2fc3913622c97209a1b2a3eeca7f835761d7223f06d3742f2e7
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical finding for a link farm containing numerous external URLs. The ML classifier also assigned a high probability of maliciousness. The document's purpose appears to be to redirect users to external websites, potentially for phishing or to serve further malicious content, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://zajinet.ru/wix?keyword=intermediate+microeconomics+notes PDF link annotation
    • https://cdn.sqhk.co/moxulofilose/YgfWgga/bus_warszawa_centralna_biala_podlaska.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411917/normal_60249339c5d6d.pdfIn PDF document text
    • https://cdn.sqhk.co/sewetotab/EjjAWig/wingsuit_flying_deaths_youtube.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386597/normal_60244abe8f672.pdfIn PDF document text
    • http://pidawiwosoda.iblogger.org/physics_classroom_dc_circuit_builder_answers.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380088/normal_5ffc30691c332.pdfIn PDF document text
    • http://mowisadewojapu.22web.org/asp.net_core_tutorial_free.pdfIn PDF document text
    • https://cdn.sqhk.co/wovupeni/6hegdZd/small_white_modern_farmhouse_plans.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420924/normal_603af7497b4d9.pdfIn PDF document text
    • https://cdn.sqhk.co/jomutepe/NfigFja/705343826.pdfIn PDF document text
    • https://cdn.sqhk.co/digipexula/wibTjhT/jimukerofudagevo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/foneniz/riwukonerazepekuwiwobem.pdfIn PDF document text
    • https://409b2d23-5c1d-402e-97df-26c0da9299b0.filesusr.com/ugd/2e3d42_d7295af9a7bb4cdea92fc18f0896f41b.pdf?index=trueIn PDF document text
    • https://f1ddcea9-c323-452c-a4d3-aaefec61e50a.filesusr.com/ugd/defd8a_de389ba1f2004c2d8b83989e452621b8.pdf?index=trueIn PDF document text
    • https://18b09f4e-de4d-4c1b-9fe6-be55c63b1c00.filesusr.com/ugd/cd81e9_376cf9f553ad4f4c9a78d63f0f79b6d4.pdf?index=trueIn PDF document text
    • https://92fa68c6-d088-48c5-94d9-776fe0504fc0.filesusr.com/ugd/5a053b_7b31cef2c92340b889727b58290a8759.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/numunenoji/76397069805.pdfIn PDF document text
    • https://bf68d742-fb98-404a-ab47-1dcf24f7df52.filesusr.com/ugd/83e7fd_8f64fffb74c24ee5845a8f939809c410.pdf?index=trueIn PDF document text
    • https://9334512a-4df1-45dc-8804-f0fa1d9e2a3d.filesusr.com/ugd/9466eb_8bcc5071f3424068b6df305b1efd9e5b.pdf?index=trueIn PDF document text
    • https://08b4a39d-fa16-4eaa-91be-ae90003cacb9.filesusr.com/ugd/237bf7_7512348243c74d6d86ef4f6529402b98.pdf?index=trueIn PDF document text
    • http://lotumimo.epizy.com/autobiography_of_yogi_in_tamil.pdfIn PDF document text
    • https://s3.amazonaws.com/godewumazek/redunufagigeka.pdfIn PDF document text
    • https://s3.amazonaws.com/xumakomowi/daninasilepobafe.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_off0000d6c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6C9 4992 bytes
SHA-256: 1adcf2cec1f4eac2a471b8a6585fcbc6327774cfc30da08e542196b75c81d806
font_01_sfnt_off0000e7a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A3 10484 bytes
SHA-256: 930d68b42b4540edc7458e923acc20ab3c5bec2f029778859a810d925c70f52c