Malicious PDF — malware analysis report

Static analysis result for SHA-256 81d868f6c85e12c2…

MALICIOUS

PDF

109.0 KB Created: 2021-05-03 20:35:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 2df69e7dcf1bc9a0f9878f27b2c91a90 SHA-1: d0085b5ff983e5ae10d295e1423602a64d7de931 SHA-256: 81d868f6c85e12c2c70b5d33a3c249c50d303a3a5d285b87eaf26a1ced4805be
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a significant portion pointing to disposable hosting and exhibiting link farm characteristics. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing. While no scripts were directly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to potentially malicious sites, aligning with spearphishing tactics.

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://dugedepap.ru/strik?utm_term=oral+b+vitality+replacement+heads+walmart PDF link annotation
    • https://cdn.sqhk.co/divojimo/OThgIon/strike_fighters_2_graphics_mod.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454164/normal_5fe984c07739c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366969/normal_60563a6a21541.pdfIn PDF document text
    • http://fefosawixamuwow.22web.org/compellent_scv3020_deployment_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/xidafigutoxa/cMcfuhE/ms_project_gantt_chart_free_download.pdfIn PDF document text
    • http://wifefavowe.iblogger.org/mafia_3_weapons_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/diwelamu/gijdfyi/chinese_man_fishing_with_bird.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/zubata/what_is_the_meaning_of_shattered_in_urdu.pdfIn PDF document text
    • https://s3.amazonaws.com/genijusemu/samsung_q7f_75_price_in_pakistan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/85a6d0dd-cb0d-400b-ac7f-76bed23b7b34/what_are_the_steps_in_system_design.pdfIn PDF document text
    • https://b3a8b944-ddec-4d17-9b53-5a1c05c66d8c.filesusr.com/ugd/314503_4e631c6d8340497ab3024c96e6825afe.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c0c724f2-10b1-4371-916e-418f388ffa8c/lista_de_verbos_regulares_e_irregulares_en_ingls_para_imprimir.pdfIn PDF document text
    • https://4a39c6c9-989b-4d11-b2d8-cc0becc7f193.filesusr.com/ugd/ef0078_afcc6bedc6204d7683ff64de2d510d31.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bf1d5be9-66ff-44ae-a7c9-b78f8b3fdacf/hunter_fan_remote_not_working_for_light.pdfIn PDF document text
    • https://s3.amazonaws.com/foneniz/architect_drawing_software_free.pdfIn PDF document text
    • https://da6a6a96-7907-4aac-bfe3-592928b14ca9.filesusr.com/ugd/39e844_2992944d97d94cbe955261181bee0bc6.pdf?index=trueIn PDF document text
    • http://samuvikakoxuj.epizy.com/99818625566.pdfIn PDF document text
    • https://8e0cabef-d481-4215-b437-8a5fc4e4723c.filesusr.com/ugd/f41140_c0c017879b3542b18d702657d3e9cd0d.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00018926.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x18926 18720 bytes
SHA-256: a30ffaae7bd98f41d39356d45f3ce1a1bd759e14955c9ebc8ad293f1b2666452
font_00_sfnt_off00014db2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DB2 5732 bytes
SHA-256: 7df4390b464cbac4c3465e292cd9bf521ae21c33275b956d31d1691bf4826cbb
font_01_sfnt_off00016110.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16110 11668 bytes
SHA-256: c4c119280f537232f66a86d67315dba73f2271db9f3d08888b459f9b5f95ba2f