Malicious PDF — malware analysis report

Static analysis result for SHA-256 44a4fdfddd6b26f6…

MALICIOUS

PDF

77.4 KB Created: 2021-05-14 05:54:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 0e10d6ab2f78187bd5240ef3e53686ea SHA-1: 9f7f41e9c30213280615d2499d6a9dbddb5c1efe SHA-256: 44a4fdfddd6b26f663791433140518dbf413af8723c0c79eff4808da85d4203a
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 hosted on disposable domains, suggesting a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were directly extracted, the PDF structure and embedded URIs point towards techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nipisod.ru/strik?utm_term=how+to+clean+lg+direct+drive+washing+machine+filter PDF link annotation
    • https://cdn.sqhk.co/fenazijeguk/hj2ghgf/fire_alarm_drill_sheet.pdfIn PDF document text
    • http://fuxezaboxekave.scienceontheweb.net/basics_of_computer_networks.pdfIn PDF document text
    • https://cdn.sqhk.co/bufilimel/ciiha1e/75077791141.pdfIn PDF document text
    • https://cdn.sqhk.co/kupujape/8hjfigl/viva_slots_vegas_slot_machines.pdfIn PDF document text
    • http://tugokutuli.scienceontheweb.net/23628530556.pdfIn PDF document text
    • https://cdn.sqhk.co/wajuletixex/cwsUQ9b/colony_brands_inc_careers.pdfIn PDF document text
    • https://cdn.sqhk.co/furugilenu/t2haXTC/pajozako.pdfIn PDF document text
    • http://volalagokiva.sportsontheweb.net/freak_the_mighty_book_review.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://sodowurivav.onlinewebshop.net/analise_sintatica_e_morfologia_das_palavras.pdfIn PDF document text
    • https://493f174a-a540-412c-bacb-e5b7b26cbfcf.filesusr.com/ugd/95bb70_81279ee31de34932aa19625b6992be5a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/aaf48365-2f87-40b8-8989-2de4d93def8c/7313552828.pdfIn PDF document text
    • https://d4bcd744-2348-4fe3-9006-05b2fcbd3cbd.filesusr.com/ugd/704566_499f8abb993f4dc0a1bf0ea4b59a8973.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/56cb90cb-3183-4213-a17c-18ce36e2efb4/does_iud_cause_bleeding_after_intercourse.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c0d3971-732c-40db-971d-b69b48899c86/33882637218.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/68c96bd5-552e-400e-90ae-90b4435245a9/how_do_i_contact_manpower.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9b830586-59ae-4479-9ef6-5a721cf3e345/mechanics_of_materials_beer_solutions_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d28977a-feed-4c9a-b0a0-110b5a3e7369/bazatosedubinujajebus.pdfIn PDF document text
    • http://kemesid.onlinewebshop.net/destination_a1_a2.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0feee7fa-c582-4c46-b163-f462e333d0f6/little_golden_book_the_poky_little_puppy_1942.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/82b03c5f-4743-4f58-ba5d-73efcdebcf57/htc_m8_charging_port_loose.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1238dbe2-ccb0-47c0-bfb4-2fd70568d69d/6261035400.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_off0000ef87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF87 5548 bytes
SHA-256: 56dd43f2739c91631110808ee7ae2c9a89dddee6edf838540a4be6daf4e9d6de
font_01_sfnt_off00010251.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10251 11084 bytes
SHA-256: ceb1b3b97cf6406b7af3c1037c59d12651aa58274a5f6c43140cbcaf87b19a01