Malicious PDF — malware analysis report

Static analysis result for SHA-256 75b4d879e71e34ab…

MALICIOUS

PDF

79.7 KB Created: 2021-03-07 02:42:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 0e94bda5e31fe6f96798919324ad8766 SHA-1: 288d5e81da65a26decb7c5176e7bbc711dff8725 SHA-256: 75b4d879e71e34abc609b9ffa2b02eb6b4c6cad7373a37bda774ddd619c8c35f
126 Risk Score

Malware Insights

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

The PDF file contains heuristics indicating it is a link farm designed to redirect users to external websites, with one prominent URL being 'https://kuzutuzo.ru/strik?utm_term=how+to+play+walking+bass+on+piano'. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://kuzutuzo.ru/strik?utm_term=how+to+play+walking+bass+on+piano PDF link annotation
    • http://sokixatov.mywebcommunity.org/what_is_keal_forged_in_fire.pdfIn PDF document text
    • http://kekewawoxugar.sportsontheweb.net/canon_powershot_sx160_is_manual_espaol.pdfIn PDF document text
    • http://jabilevij.mypressonline.com/sony_bdp-s570_firmware_update.pdfIn PDF document text
    • http://dajexori.mypressonline.com/changing_dewalt_735_planer_blades.pdfIn PDF document text
    • http://diluzadumavotux.getenjoyment.net/gotusafukadixafirep.pdfIn PDF document text
    • http://gixapedotamerow.mywebcommunity.org/76195735775.pdfIn PDF document text
    • http://winatesef.sportsontheweb.net/why_the_rich_are_getting_richer_robert_kiyosaki_download.pdfIn PDF document text
    • http://sowopezamiw.medianewsonline.com/whirlpool_washer_will_not_spin.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://44bb6ee8-a0fe-4f72-890f-0f0a2fec05cf.filesusr.com/ugd/b65acf_22807d532edb4ac88cd48a73610ef09e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/68c8b63b-e120-44f2-8dd9-b93acf3ff02c/how_to_fix_netgear_router_orange_light.pdfIn PDF document text
    • https://d6b7b3c7-8429-4d82-9d75-5d5d09e763cc.filesusr.com/ugd/a8c229_aa5cd8835263473ba809036a12f23fbd.pdf?index=trueIn PDF document text
    • https://f8ba888e-8f71-4fde-8303-550399648f4e.filesusr.com/ugd/17ce20_0cdad610659c442a980b9f6fe06df215.pdf?index=trueIn PDF document text
    • https://f3874c2d-c116-49c2-b7b6-9300dc8fc43e.filesusr.com/ugd/b11f6d_2244963e04e6457db5e48612727a6413.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zusevamasor/75154252507.pdfIn PDF document text
    • https://s3.amazonaws.com/memobofilenabon/python_for_everyone_2nd_edition.pdfIn PDF document text
    • https://9526c93a-d340-4dca-b5fd-2864ff0888c4.filesusr.com/ugd/4c3d6a_7bfa748aa9324310b841493be2fdaa8b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c8a73aa-3d72-44de-9bc3-01eafa705749/50_shades_of_grey_soundtrack_mp3_download.pdfIn PDF document text
    • https://6e229dea-1f83-4be8-8cd3-388eabd4f5e3.filesusr.com/ugd/1cfe37_04b39307693342049880a686a15729ba.pdf?index=trueIn PDF document text
    • https://8d59741e-369e-44be-b01e-8fbcb09d2d01.filesusr.com/ugd/7cefa9_9aa44184daec4c6d8ea1965d82d77dd1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/divelatoxa/aptitude_test_samples.pdfIn PDF document text
    • http://lixugafepujijoj.onlinewebshop.net/75554451965.pdfIn PDF document text
    • https://0dea665b-aaaa-42f3-a52c-f86f0fd1efa2.filesusr.com/ugd/8b9728_f97c2977ebd84043968abdfd358ea03e.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f9fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9FB 5248 bytes
SHA-256: 22399239c30a91ca4fcb4a4a488b2dec2db7103c2b8d8f1c7f86ba8467ace271
font_01_sfnt_off00010c07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C07 10884 bytes
SHA-256: 65b52ec1c00c01413edd3d68e9b746426cce3ed50e99553e2044a12fd92dab2d