Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6d050edf4a7f247…

MALICIOUS

PDF

79.0 KB Created: 2021-06-11 05:11:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 05b0734c7976f9be5da012f083f42d77 SHA-1: aca43c92551167f3b816e6024ce58b1424ff54c2 SHA-256: b6d050edf4a7f247c03336191de8f3ad1d1c3c8c386455144bb800e590844e91
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to disposable hosting and employing UTM parameters, suggesting a link farm designed to redirect users to malicious sites. The presence of these links and the overall structure strongly indicate an attempt to trick users into visiting potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • 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://krisoc.ru/pbw?utm_term=pubg+obb+file+15.0 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4378382/normal_605f82ea86089.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415334/normal_5fd99791bf64f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460063/normal_603e516d1d523.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378856/normal_601cb5403f448.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404500/normal_6035dcf6b39be.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4410965/normal_60afe8bae69db.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4374852/normal_5feb09744fe74.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485166/normal_60540fc491f88.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374211/normal_60c1aa7345542.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477373/normal_605032e4ed41d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446019/normal_603cb8052e452.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4477147/normal_60b6f4397753f.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://lekuzax.pbworks.com/w/file/fetch/144680274/how_do_i_get_medicare_reimbursement_for_shoes.pdfIn PDF document text
    • http://ruwomodanom.pbworks.com/f/how_to_recover_photos_from_google_drive_trash.pdfIn PDF document text
    • http://pamotekegopa.pbworks.com/w/file/fetch/145097082/8525423710.pdfIn PDF document text
    • http://xojifot.pbworks.com/f/taylor_fundamentals_of_nursing_9th_edition_ebook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f96fbef4-6a29-4bea-84f1-63e2e66ea4fa/49716234237.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6953cab1-956c-42e5-b488-88ce997b4294/singapore_math_2a_workbook_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/67182cfe-c62c-4858-b902-835539356cb3/descargar_libro_escudero_de_dios_gratis.pdfIn PDF document text
    • http://mevuteled.pbworks.com/f/37703101421.pdfIn PDF document text
    • http://pafunanukexe.pbworks.com/w/file/fetch/144485295/45911113789.pdfIn PDF document text
    • http://lokifasowaso.pbworks.com/f/how_to_get_more_bonus_rolls_on_yahtzee_with_buddies.pdfIn PDF document text
    • http://xuruzinijub.pbworks.com/f/valores_normales_de_amilasa_y_lipasa_serica.pdfIn PDF document text
    • http://kokoxudalux.pbworks.com/f/budim.pdfIn PDF document text
    • http://giwumekejam.pbworks.com/w/file/fetch/145097979/medolijeregidumavipafi.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_off0000e89d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE89D 4944 bytes
SHA-256: 24125512beccce182c7b0c5240082fbca19d8739f6a344c6f7239b3af40c0a80
font_01_sfnt_off0000f99c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF99C 4144 bytes
SHA-256: 065747c5ee5dd8c170b6190fcf780872acfeeb8409031402e7716cc5a06dc110
font_02_sfnt_off00010651.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10651 11532 bytes
SHA-256: 1d22c5b1201eb3da31a063df8b6e6b9217cf04af88799c88ef84b48a59d7d0ae