Malicious PDF — malware analysis report

Static analysis result for SHA-256 d637842a9c38179e…

MALICIOUS

PDF

94.6 KB Created: 2021-03-18 16:01:46 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 4826c58c82eba44b5fdb7b98fc8e823e SHA-1: 11acab861668ca229bc12f213bced7a766607f30 SHA-256: d637842a9c38179e6d512c09d4aa7c7dd128391b19ff8f5529045ed6027e4fb9
66 Risk Score

Malware Insights

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

The PDF contains an embedded URI pointing to a suspicious domain, identified as a link farm on disposable hosting. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the presence of an external URI suggests an attempt to redirect the user to a malicious site, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 4

  • 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://nipisod.ru/award?keyword=schizophrenia+nursing+case+study+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4390643/normal_6009824b2371f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407749/normal_60522d84ef770.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370265/normal_5feef9e09d161.pdfIn PDF document text
    • https://cdn.sqhk.co/zofizitene/7JkBzMQ/3541492555.pdfIn PDF document text
    • http://boxberry-24.cc/kutilisuzuzisupevlqvr.pdfIn PDF document text
    • http://bomisedoxu.mywebcommunity.org/nusunanatejeguneraginu.pdfIn PDF document text
    • https://cdn.sqhk.co/dudumadopole/cjiicSv/13738784057.pdfIn PDF document text
    • http://xilexevu.scienceontheweb.net/27951368918.pdfIn PDF document text
    • http://lezobul.medianewsonline.com/maths_olympiad_books_for_class_5.pdfIn PDF document text
    • http://nusowutevu.getenjoyment.net/94248956328.pdfIn PDF document text
    • https://cdn.sqhk.co/rusefijow/cKjfhbT/free_wifi_new_york_city.pdfIn PDF document text
    • https://cdn.sqhk.co/tipadasa/algjggE/baboxadutux.pdfIn PDF document text
    • http://nibajafij.medianewsonline.com/vozoxizaliwab.pdfIn PDF document text
    • http://hurleyshamburgers.com/lambo_urus_top_speedao9l6.pdfIn PDF document text
    • https://cdn.sqhk.co/kivipemo/uhaPgjX/fire_alarm_testing_report_format.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486368/normal_602028d01b8ee.pdfIn PDF document text
    • http://mesutilixuta.sportsontheweb.net/presidents_during_the_republic_of_texas_tended_to_coalesce_around.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/83389925-45f3-4246-92b8-94bb423bcfe6/i_want_to_enjoy_life_quotes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/45b77b79-406c-4128-be6e-a8bf20596aa6/bojack_horseman_season_5_episode_1_script.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f415c5e2-a2e9-4981-815a-1355db531685/storytelling_greek_and_roman_theatre_quiz.pdfIn PDF document text
    • http://tifavamifikas.myartsonline.com/05_jeep_grand_cherokee_bolt_pattern.pdfIn PDF document text
    • http://rupesujutiwu.myartsonline.com/willmington_guide_to_the_bible_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d09d0147-3ebf-4632-8c39-9dc1afc9f942/tom_clancys_the_division_2_review_gamespot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/372a8009-81b9-49a0-a4a0-dbff148671b0/67884675246.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_off00012649.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12649 5524 bytes
SHA-256: 8aa7b1b38705f1dd2fc7d09cbc0363182b9f3d38413e6c801fa8d9cca9e2c6fb
font_01_sfnt_off00013907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13907 10568 bytes
SHA-256: 99180a8a8f4ca31af18a1a45df542983747c5881d673efd40c0b4ab4491df2d4
font_02_sfnt_off00015d1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D1A 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333