Malicious PDF — malware analysis report

Static analysis result for SHA-256 66c8d455bb648b8f…

MALICIOUS

PDF

81.8 KB Created: 2021-05-21 23:14:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: dfb6f1cbeccaa882f195b734049fe0bf SHA-1: 5abfac123ca284e6e68c351f24b57752a41881c7 SHA-256: 66c8d455bb648b8f22da46aba019ee7fd795330c91a4e3bf309b7c81b23514c0
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 0.9994

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 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://xajibur.ru/strik?utm_term=how+to+solve+maths+problems+quickly PDF link annotation
    • https://dopesijej.weebly.com/uploads/1/3/4/6/134612330/07298a451b29.pdfIn PDF document text
    • https://pudebotajiv.weebly.com/uploads/1/3/4/0/134012430/nujomasi_tizerovaxijuti.pdfIn PDF document text
    • https://kelebewo.weebly.com/uploads/1/3/4/3/134359650/8001858.pdfIn PDF document text
    • https://mupibidegupek.weebly.com/uploads/1/3/0/8/130874042/vufurafakuna.pdfIn PDF document text
    • https://toraboretopupu.weebly.com/uploads/1/3/4/7/134769369/9527274.pdfIn PDF document text
    • https://gimogelego.weebly.com/uploads/1/3/4/6/134601730/412fd41c.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/kakekojezutok/cisco_amp_for_network_ordering_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/71a393c6-3ad5-4a42-8fc3-956bd97f337a/icewind_dale_trilogy_age_rating.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2bb45d28-1898-4aa1-ba7b-50696b5e9f7c/personajes_de_cronica_de_una_muerte_anunciada_y_sus_caracteristicas.pdfIn PDF document text
    • https://s3.amazonaws.com/nufidibodudulad/76638763792.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/decabbca-c89e-491f-8aa1-43d97f88cc93/72552674867.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cf894339-cfe4-4d92-b8b4-6fa2668b95e9/35456431561.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b97843b6-3059-429f-bdbe-1606bf24179e/models_of_the_solar_system_worksheet_answer_key.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1f4ccd2e-ec88-49c0-9b30-12f206276341/criminal_defense_attorney_in_houston_tx.pdfIn PDF document text
    • https://s3.amazonaws.com/xukirizugukugi/xuxesix.pdfIn PDF document text
    • https://s3.amazonaws.com/nowokil/blackjack_strategy_card.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d692a3c7-c0d7-44fc-9096-3b206cefef2d/16024787975.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/afd9b812-f60d-4175-9c98-af6672150ec8/59824569460.pdfIn PDF document text
    • https://s3.amazonaws.com/palikuvexake/importance_of_holistic_education.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26f6a3aa-5b70-4c60-ba85-bbce738e9231/xelabelakivojirodus.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ea13b72f-47c2-408b-a414-6600368854bb/11938737248.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/10a9199b-cdb0-4dac-85a4-d8e9e5fd0b98/will_travel_be_allowed_in_2021.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/44584513-5ac9-446c-a863-3566a5db6b6d/wadelakugasololibapozi.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010043.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10043 5720 bytes
SHA-256: 4c31e50843d625fa1593a239ba8846d0d1cfba1de64ee54854ec64e49876ff77
font_01_sfnt_off0001139f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1139F 11264 bytes
SHA-256: 10ec2aed565a821dccf41e07cbbb6ebe83abafd99cbfbea534b566b3031fd3cc