Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1271d0fca2a230a…

MALICIOUS

PDF

71.9 KB Created: 2021-03-25 12:42:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 672e56fb2f5ac9b6a721418a75f77352 SHA-1: 53aea2d5ddb756dafda9568d868d55d5802dce85 SHA-256: a1271d0fca2a230aa0e1a7d974aeeaf5271b28fe08ceb90f4ad402148f02d544
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, identified by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be directing users to a network of disposable domains, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://fokemale.ru/123?utm_term=narasimha+swamy+hd+images PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4460477/normal_60480aaed0438.pdfIn PDF document text
    • https://cdn.sqhk.co/belexewuwif/KWjfihC/zusekamujodatotatabo.pdfIn PDF document text
    • http://pigigozoruda.mypressonline.com/lexufabenogafurupitarit.pdfIn PDF document text
    • http://nesorus.mywebcommunity.org/panasonic_viera_tv_remote_volume_not_working.pdfIn PDF document text
    • https://cdn.sqhk.co/tipusuzog/hi8jhpB/18123543926.pdfIn PDF document text
    • http://rolapisi.scienceontheweb.net/wawudujej.pdfIn PDF document text
    • http://jigikujed.scienceontheweb.net/board_games_to_teach_english.pdfIn PDF document text
    • https://cdn.sqhk.co/diwamukef/tgqhghj/unicorn_run_game_free_download.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495854/normal_604503b72bbbb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488560/normal_5fe099a41520a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375531/normal_601127c759954.pdfIn PDF document text
    • http://bunagutafa.getenjoyment.net/27226116505.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419857/normal_6054fd389a59b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456686/normal_600a55cb517f2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488842/normal_5ff75b8e2ee95.pdfIn PDF document text
    • https://rifivubego.weebly.com/uploads/1/3/1/4/131407021/deperagoke.pdfIn PDF document text
    • https://komamizidunip.weebly.com/uploads/1/3/1/4/131437982/rebogizopusomo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415770/normal_6042a5091f1c3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486220/normal_601c624a8ccf0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://tosijikis.onlinewebshop.net/simple_past_tense_exercises_ingilizcecin.pdfIn PDF document text
    • http://nokejufesuw.atwebpages.com/pdf_capitalismo_para_principiantes.pdfIn PDF document text
    • http://jowosos.myartsonline.com/79936489929.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_off0000dc00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC00 5368 bytes
SHA-256: 326a7cb3379cf12613f24b1b61cab916384687f9237317bb1e2fcee4d30573fb
font_01_sfnt_off0000ee38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE38 10560 bytes
SHA-256: 4b54ba1620b6a4848a6719a40c22eca403592fdb7fc952a72267effd5036066f