Malicious PDF — malware analysis report

Static analysis result for SHA-256 543575c66804d4ca…

MALICIOUS

PDF

73.5 KB Created: 2021-06-13 09:17:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 8dd71f3ae4cb22c386087621901e67c7 SHA-1: b58f95f6fb2010f1d648d374dca774e2f30abcea SHA-256: 543575c66804d4ca1d843c71e233bb2cf5cc94c8c4f0a30f7ddda3c9b0a1ddb3
226 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. It uses a LOLBin command-execution lure. 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 0.9992

Heuristics 7

  • 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.
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://coretry.ru/pbw?utm_term=download+torrent+client+for+mac PDF link annotation
    • https://sezitoxonuga.weebly.com/uploads/1/3/4/8/134886233/wowit.pdfIn PDF document text
    • https://jujapuboma.weebly.com/uploads/1/3/4/6/134688254/bawumi.pdfIn macro / runtime command snippet
    • https://moremutinujiti.weebly.com/uploads/1/3/4/8/134865562/e9f85fa60cbc0.pdfIn PDF document text
    • https://jipuziloki.weebly.com/uploads/1/3/2/6/132695969/d55291184.pdfIn PDF document text
    • https://bulipabuwalo.weebly.com/uploads/1/3/4/1/134131868/675043.pdfIn PDF document text
    • https://pupoximoz.weebly.com/uploads/1/3/4/5/134584835/nuwopixekuwabuwizite.pdfIn PDF document text
    • https://jatuserunel.weebly.com/uploads/1/3/4/6/134682763/libopat.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408461/normal_603ef1a4dd1fb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373008/normal_606e2dd42f133.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4367279/normal_60b744218e56c.pdfIn PDF document text
    • https://futuziduxe.weebly.com/uploads/1/3/4/5/134508203/gigar-dijotipowu-refedavika-wemuvuborir.pdfIn PDF document text
    • https://junimadegerozo.weebly.com/uploads/1/3/4/0/134096607/6620ec769d632b1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479921/normal_606bcac7255b0.pdfIn PDF document text
    • https://sezitoxonuga.weebly.com/uploads/In macro / runtime command snippet
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/84e2440a-0e41-479e-bb55-63eb6cb9f219/how_to_fix_cmd_not_working.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2f17182f-dc70-4050-8e95-575e5a3d348b/36590035160.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e5cb346-e80f-46df-a72e-80a9ee0517e9/do_chrysler_pacificas_have_transmission_problems.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fe3f5a36-649b-4da2-8388-a4743eec3cc3/26526089819.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d76e118-bbe9-4cae-8f2c-3a91e85a10fb/ipad_mini_4_2020_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e0d8466-36de-4628-ba89-275dfd7ff5be/88137391243.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63b77011-28f5-4c2a-b7c9-ca9102fa1281/what_vegetables_to_plant_in_february_in_central_florida.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab9975e6-62bf-4e50-b5a3-2ed1810fedab/how_do_i_fix_corrupted_files_on_xbox_one.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd3871b0-eb87-4fb5-bd4f-591d14d9858b/whats_a_working_class_family.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9b24ce54-47af-417d-a8ed-2612fb8aafd0/11810372869.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_off0000e3d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D4 5080 bytes
SHA-256: a7fcda584ec0e4aa01821fb0817631320b211dd8237a9c5139fc5e72bb6119e6
font_01_sfnt_off0000f526.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF526 10476 bytes
SHA-256: 69e65c87f63fe754701bf1e5147a6657ccf15538ec5c59b5fd4e0f2cac45ea6f