Malicious PDF — malware analysis report

Static analysis result for SHA-256 15d58ca71cb2d496…

MALICIOUS

PDF

80.3 KB Created: 2021-04-02 20:23:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 93dbdb4dc8bfe3fc26d31628a6a44b14 SHA-1: 7383964492dcc4e10df04e049c86c31bdbbc76c2 SHA-256: 15d58ca71cb2d4969838978c766c316cd2de02771c94f9751254350a40a3249c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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 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://leonvi.ru/strik?utm_term=dna+structure+and+replication+answer+key+pdf PDF link annotation
    • http://vutunema.mypressonline.com/27148448328.pdfIn PDF document text
    • http://wotidoteked.mywebcommunity.org/kixidifojema.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/nabifovu/10682555244.pdfIn PDF document text
    • http://sopavame.onlinewebshop.net/42935270693.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2702cb18-3f1f-41be-a992-6fa1771b1590/najiwixizawuva.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/172cc14a-edc8-4980-8c38-f4a122c07bc3/what_kind_of_oil_for_craftsman_electric_chainsaw.pdfIn PDF document text
    • https://s3.amazonaws.com/sesafefanulokam/wpf_binding_combobox_in_datatemplate.pdfIn PDF document text
    • https://16fd3b15-5541-4454-9538-28daacbf497e.filesusr.com/ugd/e32576_057eb917285b4b869dbe8ebf481d9007.pdf?index=trueIn PDF document text
    • http://lipeporo.onlinewebshop.net/bsc_zoology_question_paper_2020.pdfIn PDF document text
    • http://fepapagibonu.rf.gd/27814449427.pdfIn PDF document text
    • https://s3.amazonaws.com/jalasilunaz/airtel_4g_access_point_settings_for_android.pdfIn PDF document text
    • https://5a2ada08-5b6c-402a-b0df-3636415b461e.filesusr.com/ugd/434ae6_1be35b4d87564f1da622b879a4273d71.pdf?index=trueIn PDF document text
    • https://e824aeac-d22a-4b45-bb3c-17051d6ee04f.filesusr.com/ugd/de60da_662a8b04e22c4f5baac028695d787ad3.pdf?index=trueIn PDF document text
    • http://mojokefav.epizy.com/gekemoxixinuxi.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_off0000fbde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBDE 5404 bytes
SHA-256: fb651efb7f7b024b4a2eb7b9134de3d80d504741332299ba4d5dafd8c7135540
font_01_sfnt_off00010e72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E72 11156 bytes
SHA-256: 34cd4f5e2b24e5684a3ea74e00e33207374e0fbedc0d27911ee2bc9474556553