Malicious PDF — malware analysis report

Static analysis result for SHA-256 744406fdbfc98c6b…

MALICIOUS

PDF

86.9 KB Created: 2021-04-21 15:43:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 5e706291d4d8bda0a747e55742d08834 SHA-1: fde9bcefbbe8e3075dd5db8d9fb03782edd2409e SHA-256: 744406fdbfc98c6bf6f5c9b0dc6a1ae0cd5705c8353974d786ceab7d1fb19162
184 Risk Score

Malware Insights

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

The PDF file contains a link to a known malicious redirector, identified by the heuristic PDF_MALICIOUS_REDIRECTOR_LINK. The embedded content, though heavily obfuscated, appears to be a lure related to language learning, likely intended to trick users into clicking the malicious link. The ML classifier and ClamAV detection further support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=how+to+improve+english+speaking+advanced In PDF document text
    • https://cdn.sqhk.co/rujiwujik/cnJSieL/36140657389.pdfIn PDF document text
    • https://cdn.sqhk.co/vegupujed/tgdihhf/noribovekigikibu.pdfIn PDF document text
    • https://cdn.sqhk.co/xelalizogim/UjhfjfS/uber_fleet_app_for_iphone.pdfIn PDF document text
    • https://cdn.sqhk.co/zodunoxurob/jgdihXO/37480019451.pdfIn PDF document text
    • https://cdn.sqhk.co/burexewejam/byXhgOf/game_of_thrones_beyond_the_wall_android_download.pdfIn PDF document text
    • https://cdn.sqhk.co/vigibizez/jb58yhd/animedroid_apk_descargar.pdfIn PDF document text
    • https://cdn.sqhk.co/lilaxikixo/jitQIii/waxikawifumuvijod.pdfIn PDF document text
    • https://cdn.sqhk.co/dasisogi/je4Hxge/the_cruise_line_hurstpierpoint.pdfIn PDF document text
    • http://leftoutclub.com/why_did_alliances_cause_ww1v2jnr.pdfIn PDF document text
    • http://quinzsy-studio.design/xexigufuvutupitidaxetat3yzy.pdfIn PDF document text
    • http://cookwellbakewell.com/alphanumeric_form_validation_codeigniterqc78f.pdfIn PDF document text
    • https://cdn.sqhk.co/xuwadezab/CZijgfv/28391034609.pdfIn PDF document text
    • http://pro-konditer.com/happiness_101_with_tal_ben-shaharukru1.pdfIn PDF document text
    • https://cdn.sqhk.co/rozopebak/aiegehd/walking_dead_movie_date.pdfIn PDF document text
    • http://artelamp.store/498896320953w2hh.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/b2e4fcc4-97a2-4b97-837b-9a7e9b01417e/76206633035.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/16486ada-83b3-4ee3-b47f-1a23ba093288/9457994806.pdfIn PDF document text
    • https://s3.amazonaws.com/sajezife/40255981442.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5c397bf-4a6e-44f5-ae41-bdbcae0d4a85/pubifotawefegazuwoju.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2fecbd6c-eb4c-46f5-86e6-286895eb4ff3/ferrari_f40_engine.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5589d340-6ab8-4dbb-a252-fab2b3cf920a/the_game_of_life_2_appvn.pdfIn PDF document text
    • https://s3.amazonaws.com/temujonuwu/90937866356.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_off000107ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CE 5452 bytes
SHA-256: f7c966a5f1797996b38c644178dd4ffb2f6e4b1cb9be8b3792009e887a4ae9de
font_01_sfnt_off00011a3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A3C 11040 bytes
SHA-256: 5011e0c6679ce2224892bd622ba38aa1bef4346d40ac8911175080385c6235b8
font_02_sfnt_off00013faf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FAF 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333