Malicious PDF — malware analysis report

Static analysis result for SHA-256 83cd9f4fb6cb5804…

MALICIOUS

PDF

84.3 KB Created: 2021-04-05 20:20:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 7109ab3134f307d2436fd9dc3e7f3262 SHA-1: e17fed3e58cd4d7e0eb3b7ea6b102d0c56eb7aab SHA-256: 83cd9f4fb6cb5804ea8a897a4c20a82a078fe3429a89af5ccaa241272f33bbee
196 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan distribution attempt. It contains numerous links to external PDFs, many of which are hosted on suspicious domains and appear to be part of an SEO link farm designed to lure users with search terms like 'euro truck simulator 2 key steam'. The primary malicious URL, https://gimoguvi.ru/strik, acts as a redirector to further download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://gimoguvi.ru/strik?utm_term=euro+truck+simulator+2+key+steam PDF link annotation
    • http://wobifotos.mygamesonline.org/555374636.pdfIn PDF document text
    • http://misifebofol.mywebcommunity.org/number_recognition_worksheets_for_kindergarten.pdfIn PDF document text
    • https://vefoduwuwi.weebly.com/uploads/1/3/4/9/134902927/4579703.pdfIn PDF document text
    • http://forisawidokomor.sportsontheweb.net/ccdp_study_guide.pdfIn PDF document text
    • http://garobunatuxovi.scienceontheweb.net/can_i_send_used_clothes_to_mexico.pdfIn PDF document text
    • http://lezeninimi.medianewsonline.com/el_arte_de_molestar_para_ganar_dinero_descargar_gratis.pdfIn PDF document text
    • https://vozokeku.weebly.com/uploads/1/3/1/8/131857213/kasako.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372983/normal_604d21223a9a3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468536/normal_6036b8a6bfcde.pdfIn PDF document text
    • https://sizelelam.weebly.com/uploads/1/3/4/8/134867910/siwojo-kupanutiza-vurovugasuxob-rujetobe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392237/normal_60160035393e1.pdfIn PDF document text
    • http://gosugas.getenjoyment.net/kuxedifikub.pdfIn PDF document text
    • http://kolagozisil.mywebcommunity.org/64257763512.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485579/normal_605d7fbdd5828.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/jadere/free_printable_english_worksheets.pdfIn PDF document text
    • https://s3.amazonaws.com/lekezaru/eular_guidelines_rheumatoid_arthritis_2016.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b18dacce-c925-40f1-bf03-545f027cbf2d/28638621181.pdfIn PDF document text
    • https://s3.amazonaws.com/jutenojamega/cutting_edge_upper_intermediate_book.pdfIn PDF document text
    • https://s3.amazonaws.com/purixifusipelid/graduated_cylinder_worksheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/74d7d738-87cd-40ba-9437-0982a847afa0/savojoku.pdfIn PDF document text
    • https://s3.amazonaws.com/nilafafakem/59926504897.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_off00010868.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10868 5200 bytes
SHA-256: afb8bdddbcb2734707c106d10197e384ac75f59b0c0300250d71e66f60fc1b58
font_01_sfnt_off00011a0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A0E 13012 bytes
SHA-256: bcbccc4c2ade3bbc6fba211ac8b942f09e1cb7dddcaeeb8411ac966b03f9a467