Malicious PDF — malware analysis report

Static analysis result for SHA-256 fec725f0673e2431…

MALICIOUS

PDF

174.7 KB Created: 2021-04-08 18:01:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 2d1eec16e5a01b22151ae41e9ffbf933 SHA-1: 53c0cba92d8bc1da9923729f0e9fe4247b56b55f SHA-256: fec725f0673e243157c1779026ed51290ec59a17a69cad04b27a209dc5c286c9
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable hosting, and is flagged by ML classifiers and ClamAV as malicious. The document body, though heavily obfuscated, appears to be a lure related to 'Aristotle nicomachean ethics happiness summary' to disguise the malicious intent. The presence of external URIs suggests an attempt to redirect the user to a phishing or malware distribution site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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=aristotle+nicomachean+ethics+happiness+summary PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4381740/normal_5ff8d417c6423.pdfIn PDF document text
    • http://linavaluviriv.getenjoyment.net/99257494210.pdfIn PDF document text
    • https://cdn.sqhk.co/mulepava/igrLaBD/92609974320.pdfIn PDF document text
    • https://cdn.sqhk.co/dofexoxev/iciaSge/64215206143.pdfIn PDF document text
    • http://dawexefif.getenjoyment.net/burkert_solenoid_valve.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419225/normal_5fff790e71f3e.pdfIn PDF document text
    • https://cdn.sqhk.co/vugomupuzisa/aCieict/electricity_bill_check_gujarat_pgvcl.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489245/normal_6038570f52232.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/c40cba17-d5c9-4f18-92d6-9483f4b6c6c6/52890691229.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1932871d-c651-4405-ba36-ff726847c754/29308191849.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/617d40be-20e4-4d83-a0a2-1cefde7a2f3e/where_is_the_model_number_on_a_ruud_furnace.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/300cd0c8-21ff-40d8-9438-c8ede40a13a3/kitchenaid_superba_fridge_ice_maker_removal.pdfIn PDF document text
    • http://xanedemu.onlinewebshop.net/lejifef.pdfIn PDF document text
    • http://sazurufupamaxa.myartsonline.com/apparel_production_terms_and_processes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b162d09-b8fb-4a50-9234-46a7f1d592dc/5429686546.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/214e7a47-f90e-47e8-8dfc-3358c89431d9/what_are_all_the_different_types_of_drums.pdfIn PDF document text
    • https://6f1239e7-da96-47bf-8adb-22d47a96a9da.filesusr.com/ugd/bb5a15_9d6217d6e55c4156b2acaf21c32cc729.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/39c2aa59-89fd-4fb6-86b3-9c1bcc5973b4/asus_z97a_bios_boot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/09366e61-3b12-4b6f-a8b5-9e052ba4ba5e/tintin_comics_in_hindi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/891b3c03-e211-4e3f-9279-ee270c30f2ed/lajitozegexodekisemaku.pdfIn PDF document text
    • https://e216d865-ddc7-438b-99b2-64609380b1bb.filesusr.com/ugd/7ae8b3_efda1b69e11b48fb90d5fb86f3b68a74.pdf?index=trueIn PDF document text
    • https://7ffdda70-5d62-4f0e-9eb1-843e96ef3fab.filesusr.com/ugd/8c5bc8_51a8729f55b04ff5a06bbdb37f3b1103.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://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_off00024a42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x24A42 5264 bytes
SHA-256: eaf6cb5ed258c123c27f9bd05f4ff740e408fbd013e154c154b5bf8cf415e4f2
font_01_sfnt_off00025c02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25C02 23332 bytes
SHA-256: 6a4e5cdc680d757cad60f1afed84e2e5f487ca1c4eb86b2630a7abaf1ad230ad
font_02_sfnt_off000297d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x297D1 16060 bytes
SHA-256: 2173a1880e9f774f759393e7d0d28dda91d04d8a3eae6bea41b822770b343b90