Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac3ff44f637a62af…

MALICIOUS

PDF

85.8 KB Created: 2021-04-05 02:15:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 8945664ea52c7761e70a542dfdc344b5 SHA-1: 810a674906e4b5f7cf6836e28534543c8b0ed93b SHA-256: ac3ff44f637a62af87600ac95f69832009d806bcc0496e7ac155864a2033b1de
134 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs, with one pointing to 'vilenefex.ru', suggesting a redirection to a potentially harmful site. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this by indicating the PDF is part of a link farm on disposable hosting, designed to obscure the final destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://vilenefex.ru/123?utm_term=guidelines+for+unstable+angina+pectoris PDF link annotation
    • http://nuverlites.online/boy_scout_store_oakland_new_jersey7qlmz.pdfIn PDF document text
    • https://cdn.sqhk.co/xidupesijij/egfUvhh/war_of_the_worlds_2019_streaming.pdfIn PDF document text
    • https://cdn.sqhk.co/fapolokid/3hnhcj6/smart_watch_women_fossil.pdfIn PDF document text
    • https://cdn.sqhk.co/letareximo/bMicw3r/85371692307.pdfIn PDF document text
    • http://vitetiw.getenjoyment.net/82674853216.pdfIn PDF document text
    • https://cdn.sqhk.co/nalawanuxa/Pib73hj/jawidilazusavobi.pdfIn PDF document text
    • https://cdn.sqhk.co/dubeminap/e3Ligih/tarupeteturuwas.pdfIn PDF document text
    • http://about-central.com/75313527200lulb7.pdfIn PDF document text
    • http://nonowun.mywebcommunity.org/31222369005.pdfIn PDF document text
    • http://meetsoda.club/how_to_fix_air_conditioner_not_cooling_in_car39xmk.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/8d138f4d-20cb-4db2-bf98-e0d5436800d6/15158232687.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/043a815b-1915-4005-adf1-97ebb3687498/pafonevupitukusegevima.pdfIn PDF document text
    • https://s3.amazonaws.com/sizabo/xovovo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f607b500-7256-4677-9e57-1a9877067a77/all_my_friends_are_dead_book_tiktok.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d30a4f74-f8cf-4eb7-a80b-4913196198bf/general_chemistry_linus_pauling_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/43426a90-b64d-4a46-9c10-5d16a4a70c12/notopoluwazonanugubuke.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/922a2912-7cc3-492c-b191-d5d0276005c1/36654238546.pdfIn PDF document text
    • https://s3.amazonaws.com/kawotexulozax/82727827572.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ad82dd11-2a28-4ae5-9469-99ae0477036c/jawbone_speaker_bluetooth_pairing_instructions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ca7096b-9ed5-4445-9f0e-6754f66c4505/what_is_artificial_propagation_in_plants.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/235af77a-c179-42c3-bb44-c14a9b832a82/65495932436.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_off0001031c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1031C 5376 bytes
SHA-256: 6fcce979ad6d0baa8ca0cc69e7099936db7ffe49ae8ce3d44dd7fdca49e8c0df
font_01_sfnt_off00011565.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11565 10688 bytes
SHA-256: 7a1613d14b70ec882313be9060dcc0439e956666050c58015542e17e44350549
font_02_sfnt_off00013a12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A12 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378