Malicious PDF — malware analysis report

Static analysis result for SHA-256 34107528815ea1a5…

MALICIOUS

PDF

93.7 KB Created: 2021-04-03 23:15:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: cb4826008d8c1ca9bbb0135c420ee35c SHA-1: 1b39593f128f3eb67a826639fb523cc2c71935c7 SHA-256: 34107528815ea1a59b7b44f980e80fd964effc4dcf6cb5acdbcc82bf72b5a663
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, indicating a link farm designed to drive traffic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/award?keyword=cashless+society+pdf PDF link annotation
    • https://cdn.sqhk.co/ruretibot/Hg1ixgg/zedemun.pdfIn PDF document text
    • http://feseburowikuted.22web.org/41515943443.pdfIn PDF document text
    • http://tosefabebiribow.scienceontheweb.net/where_to_watch_salems_lot_for_free.pdfIn PDF document text
    • https://cdn.sqhk.co/muzorefu/xEgfWMs/cake_maker_shop_cooking_game.pdfIn PDF document text
    • https://cdn.sqhk.co/lupekute/bwQ4mRt/grading_comic_books_near_me.pdfIn PDF document text
    • https://cdn.sqhk.co/gepabafi/aigiex5/best_reader_for_windows_free.pdfIn PDF document text
    • https://cdn.sqhk.co/molivovuki/i4jjheq/12390308123.pdfIn PDF document text
    • https://cdn.sqhk.co/dugelabomaw/IhehfQL/xisakolukasifone.pdfIn PDF document text
    • https://cdn.sqhk.co/xinefegepe/iKv48jc/viticulture_classes_online.pdfIn PDF document text
    • https://cdn.sqhk.co/remowiwa/0LRM6GE/nightmare_maker_manga_online.pdfIn PDF document text
    • http://kumululurug.scienceontheweb.net/aprender_frances_gratis.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://161abad2-7de2-49bb-9904-d6e2a620a662.filesusr.com/ugd/2eec94_fd8cb2a3c41945f4890743e2c1b1eba0.pdf?index=trueIn PDF document text
    • https://627f215e-41ba-4aa4-9906-5f9f9d117739.filesusr.com/ugd/8ab72e_3ff98fb8e76b44eca9e23aedbb3c0c9b.pdf?index=trueIn PDF document text
    • http://pidulenumasan.epizy.com/pdf_annotator_7._0._0._701_crack.pdfIn PDF document text
    • https://952d9f4b-853a-4e85-af28-23c4d489d487.filesusr.com/ugd/8db125_4213ebfa905a482eaddf029298f732a2.pdf?index=trueIn PDF document text
    • http://dasopikabuma.rf.gd/13332524770.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b4d188c-9e99-4023-9557-9f13b2c66fa3/officejet_8600_printhead_part_number.pdfIn PDF document text
    • https://aa4c2489-c93b-4667-afab-104bf5323bad.filesusr.com/ugd/8b49c6_03a50dae040549a99a0013d89d3411d4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ff09b5e3-9603-4f41-8ca0-453d8ba073b8/59171585686.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7bd65e54-038d-4b82-9478-db3e26fca196/uglies_book_plot_summary.pdfIn PDF document text
    • https://8e0cabef-d481-4215-b437-8a5fc4e4723c.filesusr.com/ugd/f41140_1ea9b4705cca43c8aefbf0cfd9fabad9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f34278ad-e99a-4a89-8e7e-082ee0e55495/37297599442.pdfIn PDF document text
    • http://zotawof.rf.gd/wiman.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_off00012d95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D95 5156 bytes
SHA-256: 82513639ea7fe78b39c15510a44366dcfb346be46230ee7bb0b4c95b00bf110c
font_01_sfnt_off00013f29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F29 12736 bytes
SHA-256: c4703e4d4900452cf72343642f54618af42c1d9c10bc63abfe8d71fce6c4fe2b