Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf3f71ad42fb6321…

MALICIOUS

PDF

99.1 KB Created: 2021-05-21 01:17:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: e896a2cbf6ccc2b07316b0b74c26ebdd SHA-1: 437a025b55e749e0aed7420ee0f094ce82ecc348 SHA-256: cf3f71ad42fb6321c9b3e8fb31b4d1c1e4a6e3b1542520b3da9f078e756bae9b
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan payload. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users. The primary malicious URL identified is `https://midufefew.ru/strik?utm_term=hannah+montana+halloween+episode+season+4`, which is likely used to deliver the final payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://midufefew.ru/strik?utm_term=hannah+montana+halloween+episode+season+4 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4463554/normal_602d89b5d132c.pdfIn PDF document text
    • https://lopowizuxo.weebly.com/uploads/1/3/4/4/134438001/zetegiwixomuwa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388842/normal_605fa325253fa.pdfIn PDF document text
    • https://palepolute.weebly.com/uploads/1/3/5/9/135963306/1476429.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383804/normal_603c1c206e5d9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495849/normal_5ffca60e63757.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489601/normal_5fe790255026b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457296/normal_5fe878916d977.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384483/normal_601179a742370.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4506063/normal_60446fbe8bd77.pdfIn PDF document text
    • https://latiniwujuxemuw.weebly.com/uploads/1/3/3/9/133997677/fba813aba810e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420260/normal_5fdc32f832235.pdfIn PDF document text
    • https://xaleratugigajij.weebly.com/uploads/1/3/4/6/134631249/kelukujuvazax-rogudozedifuno-sadulebuzake-porudenefalalat.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459182/normal_5fe53d3b34514.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/nonipesikiri/78524531340.pdfIn PDF document text
    • https://s3.amazonaws.com/metubevozisul/archinterior_vol_31.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b89cd76a-8bb1-4753-89de-704f7637b4a6/why_does_ethyl_alcohol_have_a_higher_boiling_point_than_dimethyl_ether.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4318a3c-d223-4a81-9859-81d932308f11/96749690455.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b50d4cf-f8a5-42f8-a41b-976c75d7a820/what_diet_is_best_for_gout.pdfIn PDF document text
    • https://s3.amazonaws.com/wovugi/how_to_install_epson_wf-3640.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/080200ab-f6ff-44de-98e8-d6989bba8af9/97693795938.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c7e9fb6-9a18-4cf6-be90-c79be46a4f6d/how_to_use_booster_pack_in_airtel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2544db44-eafc-4744-8217-9bf5fc4fb774/organigrama_empresa_comercial_ejemplo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5805048-030d-4af3-bd0a-e43c7f6a9fe3/why_is_biodiversity_important_in_australia.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f4b0d147-56c1-4777-8472-c87e1ef2afa5/behringer_xenyx_302usb_premium_5-input_mixer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d467b784-9e97-420e-b90f-de235a95b779/keurig_b140_descale_instructions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d4577bc-a69c-412e-a7c9-2960cd7bd67f/fezupofasaxinirenilutedi.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_off000144b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x144B8 5244 bytes
SHA-256: d68277c4d71a5a3315a604eeb78ae7a29b6d730a1ba2dd03de39820b4180700a
font_01_sfnt_off0001567d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1567D 11916 bytes
SHA-256: b7b985bcfee0065737e2af5bae16099b7253dc7511ca958a78d9849e680e31d3