Malicious PDF — malware analysis report

Static analysis result for SHA-256 f845b8a4e1f68808…

MALICIOUS

PDF

75.8 KB Created: 2021-03-20 07:19:53 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 9edda709f5ac4c93416b742bd1a53132 SHA-1: 223d4db798f917c0a46a9aaa02e789a705089f2b SHA-256: f845b8a4e1f68808452aedf2780c99ab725660465dd8d390910899dce5f9f144
186 Risk Score

Malware Insights

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

This PDF document exhibits characteristics of a link farm, with numerous external URLs embedded within it, disguised as a syllabus for the IBPS bank exam. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for SEO manipulation or phishing purposes. The presence of embedded URLs suggests an attempt to redirect users to potentially harmful sites.

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://druttle.ru/award?keyword=ibps+bank+exam+syllabus+2020+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4420454/normal_5fd994c18d6e7.pdfIn PDF document text
    • https://xixefofitajeres.weebly.com/uploads/1/3/3/9/133999179/takuxubisavigedeteta.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487632/normal_5fe9c723231ea.pdfIn PDF document text
    • https://vusukiziroge.weebly.com/uploads/1/3/0/9/130969505/f842b5c5899bd2.pdfIn PDF document text
    • https://lepatoketi.weebly.com/uploads/1/3/4/7/134732542/4822939.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369631/normal_604e15d80d037.pdfIn PDF document text
    • https://tavadubamik.weebly.com/uploads/1/3/4/4/134473349/2696538.pdfIn PDF document text
    • http://kilekapalovuzo.getenjoyment.net/86953961826.pdfIn PDF document text
    • http://xavesusefowale.mywebcommunity.org/juxavalixefegipe.pdfIn PDF document text
    • http://jerimujolegem.medianewsonline.com/alligation_and_mixture_shortcuts.pdfIn PDF document text
    • https://lopamazaveseku.weebly.com/uploads/1/3/4/6/134643240/dunogevup_desol_vudoniw.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/12819f01-aa53-491a-b4fc-5a1d2847e5ad/70716117404.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4e513110-fe5f-49f0-bbe7-f82c834d1fae/viduzimomalotiditoxera.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f96482b6-cef7-47aa-bb26-a7488914cdc4/young_life_need_talk_illustrations.pdfIn PDF document text
    • http://ledaruwevegoxu.onlinewebshop.net/key_for_schools_workbook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e13274e3-2bd6-4382-8b3a-15671275ff2a/41916994097.pdfIn PDF document text
    • https://041aa876-b65b-432c-96c0-58c8b295a4e4.filesusr.com/ugd/90d19e_0a09dc6a61184ff0b0b680fdf8a72d39.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/81ea522b-9ad2-487c-a5c7-38acd3b005dc/wukivividojewesejado.pdfIn PDF document text
    • https://a0f88182-e1f9-4a9c-ba22-d5ce004c6985.filesusr.com/ugd/2f3216_4a2ae5c4554d433cb33b4d8199fadc1d.pdf?index=trueIn 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_off0000e9df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9DF 5676 bytes
SHA-256: 6f2ee8b8b7d76cb5d3e6ae2169b513f5c33d8bcd46e9b8682663ac0ea7911071
font_01_sfnt_off0000fd2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2D 10908 bytes
SHA-256: e2bbd0260608a45eacecabcf5fc7b2514f6e86f559ba09425d42a87065487ee5