Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b1b84aad4f475d9…

MALICIOUS

PDF

77.2 KB Created: 2021-03-28 18:06:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: cf6f82b385be51148a79b90d54b201cb SHA-1: 846ebdd92895294d392653e1e2d9f50e4d04cf51 SHA-256: 5b1b84aad4f475d93a99825353b6b96e66596845b38c4f6268f5f6d429152f75
186 Risk Score

Malware Insights

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

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 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/aws?utm_term=what+happens+in+chapters+10-12+in+lord+of+the+flies PDF link annotation
    • http://flebolog24.com/how_to_write_a_movie_review_formatmwzxv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370053/normal_6054dc34dbad9.pdfIn PDF document text
    • http://thehensleys.org/how_to_start_a_second_line_in_excel_cells6vqk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456676/normal_6017aa1933e53.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460057/normal_60299713924c2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449185/normal_602b9c0bdf620.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470521/normal_60217a1107f82.pdfIn PDF document text
    • https://cdn.sqhk.co/vemegunir/4bgiihd/53024072397.pdfIn PDF document text
    • https://cdn.sqhk.co/joninopi/jfYjcgg/bollywood_music_video_hd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477638/normal_5fe1a83cb9127.pdfIn PDF document text
    • https://cdn.sqhk.co/jonimaze/eKieGje/infectious_mononucleosis_test_interpretation.pdfIn PDF document text
    • http://pestore.pro/jobebokapej1sqk.pdfIn PDF document text
    • http://znakomstva69.space/85089694307358i2.pdfIn PDF document text
    • http://instasale.company/rinnai_electric_panel_heater_manual9cziv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464878/normal_60233281d108d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://22449060-8e30-4723-8828-967625cce342.filesusr.com/ugd/eddc50_6a4060a5831b482688f89bdd81103f94.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4df24c95-aa63-4359-a3bc-0f7affecd003/what_to_do_when_he_reappears_after_disappearing.pdfIn PDF document text
    • https://f05e0dbb-21cf-40ea-8b71-00b8d6f49a3b.filesusr.com/ugd/b09e1d_0c1e2edce41e43749c6b8cdab28457ea.pdf?index=trueIn PDF document text
    • https://8c56b32b-3398-45d6-9c0b-b55146621f16.filesusr.com/ugd/6924eb_634c9eb4626941479eeb3429e927dfdd.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e598e66-0ae4-4b5b-b76c-32eecbcd3086/57965119611.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_off0000ed6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED6A 5612 bytes
SHA-256: f2bfc205c585378570d84eb15f4c34ea59b1d6a21353be25592bdadeea3c42ea
font_01_sfnt_off00010096.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10096 10904 bytes
SHA-256: 5c96018ef70d18abe9381167ddd21bc9ad19635464170928cb4d6a0f3aac53e6