Malicious PDF — malware analysis report

Static analysis result for SHA-256 57830410f046e359…

MALICIOUS

PDF

74.7 KB Created: 2021-04-03 20:28:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: a5c99c7a6a16c12e510997227880e4f3 SHA-1: 8704a223556289210114e4d3b496eaa5d978157c SHA-256: 57830410f046e3598bb9bd38f89f3dc968a88f18c55058f497d81119b941b04b
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 0.9998

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://vilenefex.ru/award?keyword=biological+anthropology+3rd+edition+pdf PDF link annotation
    • https://cdn.sqhk.co/nixivezez/ihb3igT/3098487781.pdfIn PDF document text
    • https://cdn.sqhk.co/jotoselu/n7Tjfgf/demigod_definition_synonyms_and_antonyms.pdfIn PDF document text
    • http://everydays.space/sakapojugxj9z.pdfIn PDF document text
    • http://spain50off.info/tofuxivesaxiz8b166.pdfIn PDF document text
    • https://cdn.sqhk.co/mowefakura/gjehGmY/intellij_generate_jacoco_report.pdfIn PDF document text
    • https://cdn.sqhk.co/diratukuz/UU5ysfH/15316563314.pdfIn PDF document text
    • https://cdn.sqhk.co/mivijigonof/jjuiawI/met_police_officer_salary_2020.pdfIn PDF document text
    • http://alexsaf.ru/67831134787qe4pw.pdfIn PDF document text
    • https://cdn.sqhk.co/tosilura/jjjhjaB/36395423677.pdfIn PDF document text
    • https://cdn.sqhk.co/vesagivara/jiWcYid/pekakanafudifap.pdfIn PDF document text
    • https://cdn.sqhk.co/zanudiwageg/xjdhaij/fun_pc_games_free_no_download.pdfIn PDF document text
    • http://xavadomitom.iblogger.org/how_do_i_sleep_with_a_broken_femur.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/c859df5c-887b-4133-a70b-92ea506b1054/craftsman_self_propelled_lawn_mower_how_to_start.pdfIn PDF document text
    • http://kedogevakubonog.epizy.com/86586502210.pdfIn PDF document text
    • https://5fa60de5-32ab-41ac-ba65-77330e21e623.filesusr.com/ugd/2e16aa_44dc97a0591445cb9435925c349b15e8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4590bef6-f853-4cca-91b8-8df3188f1271/how_does_the_cohesion_tension_theory_work.pdfIn PDF document text
    • https://18cceff7-6d50-42ec-9d85-67184b61345e.filesusr.com/ugd/8c2e83_62374ef23346485b93b46912e44e26c5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a8c6f995-ca9d-4277-a656-dcb703be7bec/1_police_plaza_nyc_directions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0172225-917c-41c4-8951-30ce5304dbde/bulova_precisionist_96b175_battery.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_off0000e327.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE327 5552 bytes
SHA-256: 4a0f3557d91abaedd27682e7de8a6575e7265f0152bf279d07db8feb3d6e593b
font_01_sfnt_off0000f619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF619 11592 bytes
SHA-256: ab2b5e947d21db0ad2c55cd029f5c73cf04c8829687f1478dd11058215149006