Malicious PDF — malware analysis report

Static analysis result for SHA-256 b733113baacae275…

MALICIOUS

PDF

87.7 KB Created: 2021-04-06 06:46:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 9bc816bba0f350f0eebf62c69a310f2b SHA-1: 133ab7a8a2b35abdf467c065f3b1d32cd3229c50 SHA-256: b733113baacae275a49b2a7c36fa49643ea03f24421746060637500edbd39adf
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • 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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://zajinet.ru/strik?utm_term=what+time+does+death+note+take+place PDF link annotation
    • https://cdn.sqhk.co/fafojipedul/2gdhdig/cdc_flu_vaccine_sheet_2018.pdfIn PDF document text
    • https://viworisexefu.weebly.com/uploads/1/3/4/8/134885507/c4225.pdfIn PDF document text
    • https://ligunoko.weebly.com/uploads/1/3/4/3/134308404/0cba77c0cb4da70.pdfIn PDF document text
    • https://widetidutu.weebly.com/uploads/1/3/1/4/131453832/mofabelojo-vigam-rovunosutufas-karij.pdfIn PDF document text
    • https://nutiduvurenomal.weebly.com/uploads/1/3/4/6/134681926/tetojataxiluvozo.pdfIn PDF document text
    • http://girepodemaz.getenjoyment.net/alexandria_moulding.pdfIn PDF document text
    • https://boloxekovo.weebly.com/uploads/1/3/2/6/132681585/musor.pdfIn PDF document text
    • http://lajafago.medianewsonline.com/sybex_cisa_study_guide_4th_edition_free_download.pdfIn PDF document text
    • http://nalodorepuwag.getenjoyment.net/escndalos_ticos_bernardo_kliksberg.pdfIn PDF document text
    • https://cdn.sqhk.co/lewulula/M2icrig/translate_english_to_japanese_romaji.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/283a6708-6a46-4028-895b-776bcf1f17d3/16523929296.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/890eb177-c2ca-4fb4-bce8-79b5c8d8afe4/how_do_i_copy_and_paste_on_my_keyboard.pdfIn PDF document text
    • https://f7690f66-1871-4559-97e0-239dee5b15da.filesusr.com/ugd/d2cc1f_21f0717d6fb6422faca8e26b00589cea.pdf?index=trueIn PDF document text
    • https://af18ad75-7652-4b25-b9e0-8da5fded0af1.filesusr.com/ugd/529385_7619449764e24a94928de88e7da122c4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f941846b-e897-4d77-b1ca-19644ff0f27e/high_pointe_microwave_convection_oven_owners_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd6262e6-5481-49b8-968b-ba9028a7b855/are_speed_queen_dryers_gas_or_electric.pdfIn PDF document text
    • http://xonolori.atwebpages.com/68699586227.pdfIn PDF document text
    • https://80d0ab3e-5d82-4547-8f02-ffe19150e389.filesusr.com/ugd/776b9b_8160b878625b44b4875aec5807e3f4ed.pdf?index=trueIn PDF document text
    • http://xevijojikutep.onlinewebshop.net/attestation_sur_l_honneur_990i_gan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4068ef1b-9656-478a-8c31-3a0502e76de5/good_books_on_the_history_of_china.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f3f8025-f5ba-41be-ae7c-e01db31aa994/laxixupa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/df097179-3e8a-4c32-826b-67caaaa3d837/76763712153.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2d1f2577-ff78-46ef-9df5-564a28e0bd06/6704143668.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c757256c-23e0-4601-80d7-a48d546a87d8/judivimatun.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000108c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108C8 5080 bytes
SHA-256: 056c3fa272d93d1625a970a524d2150d670a2d6d9ab22b312dab4492b538a65b
font_01_sfnt_off000119f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119F9 11576 bytes
SHA-256: cc02c29ec14fb2316ad70c0aab2cfacd6f77f7c311d0dd4108a98ba1256589b4
font_02_sfnt_off00014184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14184 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176