Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1bb4ce37914d5f3…

MALICIOUS

PDF

84.9 KB Created: 2021-04-11 21:04:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-28
MD5: d5c05fce83f51590b20c87fda5c459f6 SHA-1: ee998b084c780a95453e0ec4a6ebabbb6e0f8b8d SHA-256: c1bb4ce37914d5f3e0c24621885fca5d51d3859ebd3d187eba5b4e16062275e2
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristic analysis revealed it functions as a link farm, embedding numerous URLs pointing to potentially malicious content. The presence of external URIs and the 'link farm' heuristic strongly suggest an attempt to redirect users to phishing or malware-hosting sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://pelibifir.ru/strik?utm_term=maximum+ride+books+anime PDF link annotation
    • http://hiziryigit.online/saris_cycleops_fluid_bike_trainer_reviewkrcee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500910/normal_5fe9210fdbd9a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488335/normal_603f4c63a379e.pdfIn PDF document text
    • http://namabal.scienceontheweb.net/internal_audit_case_study_questions_and_answers.pdfIn PDF document text
    • http://lonemap.medianewsonline.com/datasheet_arduino_uno_portugues.pdfIn PDF document text
    • http://vumamanepu.sportsontheweb.net/74972466909.pdfIn PDF document text
    • http://belplitka.ru/starlink_internet_ratesef378.pdfIn PDF document text
    • http://woxuruko.medianewsonline.com/vifenupufapimefajamerus.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4494166/normal_601d0a83d2fa1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://rexefobixavater.myartsonline.com/ketugogawodufupabu.pdfIn PDF document text
    • https://s3.amazonaws.com/nezanurugega/pubiwuba.pdfIn PDF document text
    • http://xesijapapun.rf.gd/zipimuwenefi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/108a7141-5fdc-4627-82ed-ad5447f4ad5a/xefeziwe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/41291ec7-1831-4e9f-9e67-b0086095159a/what_size_is_mini_football.pdfIn PDF document text
    • http://woruwewuxiv.rf.gd/practical_thermal_design_of_air_cooled_heat_exchangers.pdfIn PDF document text
    • http://jetumodegupejit.rf.gd/werubuleli.pdfIn PDF document text
    • https://s3.amazonaws.com/pululusodogi/compose_piano_sheet_music_online_free.pdfIn PDF document text
    • https://s3.amazonaws.com/gorajikunobixi/formal_business_letter_format_on_letterhead.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c842738-454e-4615-8a58-f213d7b6b107/94939566882.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f2ccb5c9-3945-4070-949e-5f6a4ff5e31f/ripexuzo.pdfIn PDF document text
    • https://s3.amazonaws.com/patotale/piwenewulufetategu.pdfIn PDF document text
    • http://dokilenosabani.rf.gd/gijutafofagepopul.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f974.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF974 5216 bytes
SHA-256: 9a65497148dd4360ab7b4fbb18613e9ada01599a8e6528daa1eecef4c6ebdc35
font_01_sfnt_off00010b29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B29 10944 bytes
SHA-256: d10148884a9640098e4954f51c6f11d5bbfea6a7f14ca24d918c7be5056a1237
font_02_sfnt_off000130e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130E1 16060 bytes
SHA-256: 503f5200e83b189a546b6c6e1d808633a9135186956fe76ff9bd78de3d91e3c6