Malicious PDF — malware analysis report

Static analysis result for SHA-256 4daf8da4354f8fcd…

MALICIOUS

PDF

77.4 KB Created: 2021-04-01 10:02:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: cebb92a0192cb899e0606a04c76ae028 SHA-1: a93255713c4ce9165846c9e090ef22d51bedad28 SHA-256: 4daf8da4354f8fcd6d8c603619d45f054973fad9576bccb4995c67670c345689
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with at least one pointing to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The document body is heavily obfuscated and unreadable, but the presence of malicious links is a clear indicator of an attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crophysi.ru/strik?utm_term=walter+riso+wikipedia+libros In PDF document text
    • http://hurleyshamburgers.com/where_to_get_tracfone_data_cards0ie4h.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453560/normal_6031706ab099a.pdfIn PDF document text
    • http://trydouche.xyz/what_is_the_prefix_in_the_medical_term_microbiologistyr5nc.pdfIn PDF document text
    • http://kupiokno.su/conflict_resolution_steps_in_marriagevskpm.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477183/normal_603eb0f776dc6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366397/normal_5fe3a59cf2611.pdfIn PDF document text
    • https://cdn.sqhk.co/povuguzuloga/6tigPig/photomath_online_with_solution.pdfIn PDF document text
    • http://xafawotilujos.mypressonline.com/beseluzisonipasiremu.pdfIn PDF document text
    • https://cdn.sqhk.co/kezixowog/Ufegdie/ginezojozupoduluja.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455399/normal_603f52c4ad6db.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/5b39937b-1476-48b5-ab29-f6b38b94363b/kipubat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f77a1e9-032b-4b57-9af2-dafde594c5c0/free_download_conexant_high-definition_audio_driver_for_windows_10.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb58aa5b-ba54-442b-b1eb-d6183c7c5b47/how_did_alliance_systems_contribute_to_the_outbreak_of_ww1.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a43d51a2-9fcd-49b8-99cc-d4bc58acb450/briggs_and_stratton_small_engine_repair_manual_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d83a67b1-3c90-48a4-b480-1e5984a0c940/66642358168.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4289aeef-3f2f-4434-bba1-4e24d3e420f2/what_is_the_best_time_to_pray_salatul_istikhara.pdfIn PDF document text
    • http://suruliloxapesas.myartsonline.com/princeton_review_sat_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9cd0f39d-7e4c-4700-a121-7ed7d3feded3/review_of_distance_formula_midpoint_and_slope_worksheet_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8eb4cc4e-7627-4453-87df-47c6856443aa/fobopoz.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_off0000ef06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF06 5260 bytes
SHA-256: fba95eb9b116184c06b4257e4e3e2aa4ec2227ee6dfebc216f870d3ee2ae6f3f
font_01_sfnt_off0001010d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1010D 11668 bytes
SHA-256: be6970f37aa721c18c422f1a9ceca836f45b3aa5a859c113b8893680e7d3603a