Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ef4e7834127cc63…

MALICIOUS

PDF

80.2 KB Created: 2021-03-09 12:56:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 848d94eb5bb61482aacf212583e8093e SHA-1: 5b3931c80b88ecf261ac80d116fee8f9b9417154 SHA-256: 6ef4e7834127cc635094eb4405f614cf7130bcdf7a731852f1738f0cdadbbd81
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://kuzutuzo.ru/123?utm_term=free+community+service+hours+log+sheet PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4489411/normal_5fec35dbc3a65.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446937/normal_5fc6692a7bdeb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4372987/normal_5fcd41c4eeb0a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447263/normal_5fc5992837053.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413458/normal_602a0cadcf812.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/a5f60295-1735-4aad-b28f-0caadbe789a3/7080051107.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11233edd-2e59-467d-abb9-caeb0f26396d/kegewowurilidabizuromenab.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63431605-92d9-4262-890a-acc769911496/12774712339.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d0cb9b95-2554-4500-afdf-b424a9321826/a_song_of_ice_and_fire_music_download.pdfIn PDF document text
    • https://11ca5eb4-0abe-4d5d-8073-3f36f6088e80.filesusr.com/ugd/8b62d8_cc24a4b1281342f79cf8c4e0ea95eefa.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/508ffdef-1c38-4536-9b2c-619f0ec70789/2014_chrysler_town_and_country_service_manual.pdfIn PDF document text
    • http://pejatopofir.rf.gd/chrysler_voyager_2008_owners_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/67aaa19f-1c07-468b-9f1f-9e4d4d6a6fec/what_are_the_extra_fees_on_allegiant_air.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/39661fe1-7bb3-45b4-a978-28ac43a54b6b/how_to_thread_kenmore_ultra_stitch_12_sewing_machine.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/68bdf157-b7fa-4845-ba50-d607b23b7165/did_project_x_happen_in_real_life.pdfIn PDF document text
    • http://busugotuwege.epizy.com/little_fires_everywhere_episodes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0e7c7c3-c687-48a1-bcdd-4bf14f9292e8/que_significa_soar_con_una_cucaracha_en_la_comida.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8197396-c6dd-4f69-8605-a0be5f5b4ec1/xovoxu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1ad7b1ea-41e6-49f7-a8d5-194c133d1471/zakojirurumen.pdfIn PDF document text
    • https://c4e42e93-254c-4ba8-b495-737f84002742.filesusr.com/ugd/ddb60a_77d9530521a74193afe3d217c60a32ee.pdf?index=trueIn PDF document text
    • http://xelefufod.rf.gd/71159541553.pdfIn PDF document text
    • https://a8a70d16-e3f0-4805-b115-4d8c62c40b57.filesusr.com/ugd/82e28d_254a2b7b3ec5426aa93c8c54fff28659.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f30c9b23-eece-42ab-8dc6-086a41949d8f/how_to_structure_a_chapter.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_off0000fd87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD87 5120 bytes
SHA-256: 64fb25c006f1920d449d4a63d6d82c860289bfd798f0848c7d6aef8360979aac
font_01_sfnt_off00010ee3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EE3 10728 bytes
SHA-256: a23656447ffadd2d2ad9556240bd5dd0bff4cce5bec6f30d72d2f425e08ed37d