Malicious PDF — malware analysis report

Static analysis result for SHA-256 40513b718f1a46b3…

MALICIOUS

PDF

148.4 KB Created: 2021-05-17 12:46:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 739280a79260edb4ce50c44a44b1c538 SHA-1: 56d9a41c2863c0ae6050245ba01bad677ef5a521 SHA-256: 40513b718f1a46b343c5d1506da6fc9fef11edf0049839a2fd3d6052b0e67c17
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with at least one pointing to a suspicious domain ('kuzutuzo.ru') and flagged as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kuzutuzo.ru/strik?utm_term=english+literature+teachers+in+sri+lanka PDF link annotation
    • http://fortysgjdk.fun/is_crossfit_good_for_weight_loss_redditjmhfw.pdfIn PDF document text
    • http://iciko.xyz/find_attached_the_filled_out_form92339.pdfIn PDF document text
    • http://xilexevu.scienceontheweb.net/oral_b_toothbrush_heads_costco_uk.pdfIn PDF document text
    • http://chelamela.org/punjab_college_admission_form_2019ilqjq.pdfIn PDF document text
    • http://copyrightproblem.com/asma_bronquial_pediatria_2018jwrks.pdfIn PDF document text
    • http://tumbochka.space/muvozumamiribakb95m.pdfIn PDF document text
    • http://pebonemariv.mypressonline.com/color_by_number_preschool.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://1eb42bdc-3da6-4b32-b75f-4382f1721f8e.filesusr.com/ugd/35474d_3130e5d151564840b87a2dd0fec5229a.pdf?index=trueIn PDF document text
    • http://zaduzos.myartsonline.com/definition_of_business_research.pdfIn PDF document text
    • https://s3.amazonaws.com/seriposuj/how_to_forward_calls_on_panasonic.pdfIn PDF document text
    • http://medexode.atwebpages.com/how_to_read_financials.pdfIn PDF document text
    • https://37e0f79d-b0c1-4727-b76d-5b759c81288f.filesusr.com/ugd/9c66ff_62d7e37c759d4719a71857439555507c.pdf?index=trueIn PDF document text
    • https://8b2103c5-345b-48fd-98e3-f19c90c4efd0.filesusr.com/ugd/0e2875_7aa888009cb0450fb5841d016ecf955f.pdf?index=trueIn PDF document text
    • https://899154e9-876a-4ab4-94d5-c8ef2aed10f2.filesusr.com/ugd/dcf9ad_4b631f1022654e0e9e7051eb5e051f23.pdf?index=trueIn PDF document text
    • https://0c1adbbe-b65a-4c28-9da2-87cea21e0636.filesusr.com/ugd/496951_99d8edd9f19048b5a33d95226c66660c.pdf?index=trueIn PDF document text
    • http://vafitinupisojud.onlinewebshop.net/wusofozimomab.pdfIn PDF document text
    • https://s3.amazonaws.com/pululusodogi/wasilanes.pdfIn PDF document text
    • https://s3.amazonaws.com/fibesezati/41381533882.pdfIn PDF document text
    • https://s3.amazonaws.com/wovugi/futejixalowutejepuniwum.pdfIn PDF document text
    • https://3f735f5a-cd1c-4288-bd93-adeff6e084d9.filesusr.com/ugd/bcc0e4_35fd1231e31f46a6bc08ad4fad14f20b.pdf?index=trueIn 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://sinhala.sourceforge.net/In PDF document text
    • http://sinhala.cvs.sourceforge.net/viewvc/*checkout*/sinhala/sinhala/fonts/CREDITSIn PDF document text
    • http://www.gnu.org/licenses/gpl-2.0.htmlIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001c3c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C3C3 5084 bytes
SHA-256: 7fe4f83c3582ecd0aa738273ee3d82f32ea5d71a9fca3782ad1574d1d9994e32
font_01_sfnt_off0001d4cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D4CD 28124 bytes
SHA-256: 507afa13cfd8e78f1aa6113db076ed8dc8af2d891de97590fcfebfd997aa1fb8
font_02_sfnt_off000218ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x218CA 13780 bytes
SHA-256: 8948782a9335797b83bef31d58fdf82f2500145eb44cfd7385c97b67add4bd9a