Malicious PDF — malware analysis report

Static analysis result for SHA-256 c894fc8236989c52…

MALICIOUS

PDF

77.6 KB Created: 2021-03-25 07:42:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 611d6dc4cff5bd5b2c3bbec54b498fb8 SHA-1: 2fcfe590568c3546c72ccf8c6edc5886afb585b7 SHA-256: c894fc8236989c524a7ec48b795b92ccb9cf3d4a0e0518d5f69ceddab2583dbc
126 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains or link farms, indicating a likely SEO manipulation or content distribution scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to potentially harmful content or facilitate further infection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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://xezojetit.ru/strik?utm_term=what+is+the+role+of+an+usher+in+an+event PDF link annotation
    • https://cdn.sqhk.co/lopijikuvi/drijbge/7105388527.pdfIn PDF document text
    • https://cdn.sqhk.co/xavonepez/3HLkknH/fun_race_3d_mod_apk_latest_version.pdfIn PDF document text
    • http://fagumawegoleleb.mypressonline.com/14195089051.pdfIn PDF document text
    • http://vavexefane.mypressonline.com/algebra_2_review.pdfIn PDF document text
    • http://zogometemo.sportsontheweb.net/19735294291.pdfIn PDF document text
    • https://gexaxiwiwa.weebly.com/uploads/1/3/4/4/134480231/kabanika.pdfIn PDF document text
    • https://xijadetula.weebly.com/uploads/1/3/5/2/135296157/5075523.pdfIn PDF document text
    • https://cdn.sqhk.co/gewewoturila/agjicql/zepeto_pc_download.pdfIn PDF document text
    • https://cdn.sqhk.co/xaranoraf/jhhja8d/34567268349.pdfIn PDF document text
    • https://vevumugenewasu.weebly.com/uploads/1/3/0/7/130776279/sufulozumavet.pdfIn PDF document text
    • https://wurixexaf.weebly.com/uploads/1/3/4/8/134865586/9486101.pdfIn PDF document text
    • https://cdn.sqhk.co/tazakabebilo/sGhgdhj/combat_flight_simulator_2_no-_cd_patch_download.pdfIn PDF document text
    • https://cdn.sqhk.co/waganozusi/5jf94hb/62625253574.pdfIn PDF document text
    • https://cdn.sqhk.co/zezinojox/Hhhjjgh/retroarch_roms_ps_vita.pdfIn PDF document text
    • https://cdn.sqhk.co/zesozote/whiidii/zinakagifesed.pdfIn PDF document text
    • http://korixoludofuguk.scienceontheweb.net/list_of_acronyms_and_abbreviations.pdfIn PDF document text
    • https://cdn.sqhk.co/savageven/ORQhhlo/vosozizogefuvaz.pdfIn PDF document text
    • https://roxuxafuz.weebly.com/uploads/1/3/0/8/130813852/8befa7ccfebf091.pdfIn PDF document text
    • https://fovokifijinibe.weebly.com/uploads/1/3/4/5/134582558/2440199.pdfIn PDF document text
    • https://cdn.sqhk.co/bulelovuroga/dVAHcjj/hungry_shark_evolution_mod_menu_2020.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wavexijazibivat.myartsonline.com/xinumotekulutoxes.pdfIn PDF document text
    • https://28ae28a3-27cc-4d38-be83-0de1f6925f83.filesusr.com/ugd/454016_11b4f27319da438da5d29b369ffaa5b3.pdf?index=trueIn PDF document text
    • https://ecf8b3bd-8201-449f-a39c-156acd88681e.filesusr.com/ugd/97634b_ff0072f09ce6479699c14834cc0c503d.pdf?index=trueIn 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_off0000f156.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF156 4928 bytes
SHA-256: 4436e57901a945a69e538de550cd519ec6a3f5249b615f3a4c981eaf25a8fbb3
font_01_sfnt_off00010223.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10223 10784 bytes
SHA-256: 8b718ea72d271b680a4d931786e99a7c10fd822afaff1d9ebe45206f846c0f41