Malicious PDF — malware analysis report

Static analysis result for SHA-256 b35834f0ea495762…

MALICIOUS

PDF

78.8 KB Created: 2021-03-14 13:49:24 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: ef4e967fa6620bb986b24e02d9c5193c SHA-1: f7969fbc6757e8152c3b66bdad00ccf3f1fcbeed SHA-256: b35834f0ea495762625dc8315e86ed19ccc7b98cb26a0dbfc4b850c4d728ba31
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to disposable hosting, indicating a link farm designed to distribute malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to host numerous URLs.

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://nipisod.ru/strik?utm_term=how+to+crochet+for+beginners+left+handed PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4407314/normal_5fe03b6677fa7.pdfIn PDF document text
    • http://adminhalil.com/97023423963iap64.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402963/normal_601dc6be957eb.pdfIn PDF document text
    • http://xibesofene.22web.org/bujunepugotolelavenatex.pdfIn PDF document text
    • http://gagimubu.mywebcommunity.org/football_manager_handheld_2013_psp.pdfIn PDF document text
    • http://danupesokel.iblogger.org/1st_grade_literacy_worksheets.pdfIn PDF document text
    • http://garantiya62.ru/158233948121mhl9.pdfIn PDF document text
    • http://ufenmac.com/clases_de_sistema_operativo_androidwedii.pdfIn PDF document text
    • http://tcerkovniekupola.space/mokomineliredibiforobec7x0q.pdfIn PDF document text
    • https://nikovazof.weebly.com/uploads/1/3/2/6/132682709/8dbef61cdde7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460266/normal_6009e9d3d5bf4.pdfIn PDF document text
    • https://jiwalevimube.weebly.com/uploads/1/3/4/8/134870165/zogogakulabad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490376/normal_60164e85283ca.pdfIn PDF document text
    • https://labimatejodo.weebly.com/uploads/1/3/2/3/132302966/6061321.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://jofanemapax.epizy.com/annabelle_2014_tamil_dubbed_movie.pdfIn PDF document text
    • http://kinapemib.rf.gd/82854037470.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a635106d-6241-42e4-8311-83b9b8240ec5/61877737180.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f001e9a-4804-4043-b5c2-28b50d181cd4/vuraxo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc21f706-2827-4f32-9c0b-f34cf6811c99/the_measure_of_man_and_woman_human_factors_in_design_revised_edition.pdfIn PDF document text
    • http://mawokale.myartsonline.com/wordly_wise_3000_book_6_lesson_17.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b594c521-cef5-40dd-99b0-a378eae66f2a/gofadageridixejozebovox.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9659e70f-8233-4aa6-aeb0-76f9557ef04f/pals_menu_rogersville_tn.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_off0000f5f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F2 5476 bytes
SHA-256: e80055ba0f74f5d005e1ccd592609af4efc20a42f06708acff37a6678b9d25cf
font_01_sfnt_off000108a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A0 10716 bytes
SHA-256: 04d4d68b02d0d691fd382ca83e8d7de67e1f1a4aa7d98e93a763f454deeaa28f