Malicious PDF — malware analysis report

Static analysis result for SHA-256 21443dafa91be6f0…

MALICIOUS

PDF

70.0 KB Created: 2021-06-11 21:26:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 3a679a43fbd2ff853f6852b0f3c62ffb SHA-1: 551c10aef47ff39032f3e3cd97fa87bf79e3a844 SHA-256: 21443dafa91be6f01641ffa297cb8a5283966293b3e2cc1c2482afddbb6c25b3
126 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable domains and employing UTM parameters, indicative of a link farm or SEO spam campaign. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the PDF structure and embedded links suggest an attempt to redirect users to potentially malicious or unwanted content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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://drafthe.ru/pbw?utm_term=silent+hill+wii+rom PDF link annotation
    • https://dezuximoloxesar.weebly.com/uploads/1/3/1/4/131410685/9d48720f.pdfIn PDF document text
    • https://linekepev.weebly.com/uploads/1/3/4/0/134041162/4d78516b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://leviwim.pbworks.com/w/file/fetch/144909525/cadastral_surveying_books.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/902ebe32-cc0d-4434-a330-03320b5bfba1/55063509218.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be3c52b4-c24b-42f8-bfe1-92b56287a934/nivel_de_lectura_inferencial_wikipedia.pdfIn PDF document text
    • http://vaporezikumu.pbworks.com/w/file/fetch/144726552/97499940788.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb07885a-2493-4db4-8ecb-9b70074f7e63/army_mission_analysis_brief_ppt.pdfIn PDF document text
    • http://febamizilaw.pbworks.com/w/file/fetch/144893895/diwolozemavules.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/62fd06e2-a6b2-4bf6-baf3-36fa4b2aae8e/votufonifekililivisibuma.pdfIn PDF document text
    • http://kuxuraroj.pbworks.com/f/3_word.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/159c6001-7da5-411e-8b1a-a403747670a2/83685782767.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e86b654-a285-4ee4-9ffc-005fb32d6d9d/cuddeback_camera_settings.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/78c74d65-e967-4c2a-8004-295bb392471b/xowogu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6c9f3f31-b6e0-4e71-83e6-0fad1182390f/english_grammar_rules_and_usage.pdfIn PDF document text
    • http://betosaxugawi.pbworks.com/w/file/fetch/144790179/halston_show_soundtrack.pdfIn PDF document text
    • http://jotoxipigi.pbworks.com/f/pexoximamigeloxusezap.pdfIn PDF document text
    • http://jagimikat.pbworks.com/f/can_you_make_fried_pies_with_pie_crust.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9be25a5c-18dc-46d3-ae14-5fcc9c7c0bf3/29684280236.pdfIn PDF document text
    • http://tovovojufa.pbworks.com/f/watch_order_marvel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c7ac5d1-f73e-4675-a3bd-747ad0a954a5/josazekejivixa.pdfIn PDF document text
    • http://lonazetubuz.pbworks.com/f/jewezebumonesotabazowoz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/01457fb7-c73d-427b-a47b-08d55fbd16c4/arduino_mega_2560_datasheet_francais.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_off0000d17a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD17A 4732 bytes
SHA-256: ae5be32b32366e92eade7efc8f56389f24231f9729e20261cd8e1a676ead875a
font_01_sfnt_off0000e176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE176 12592 bytes
SHA-256: 437c42d950ddd3fdcea5235a1169a64061c23d52e24bcb5daccc2513da6de3e1