Malicious PDF — malware analysis report

Static analysis result for SHA-256 631a0cafae440c68…

MALICIOUS

PDF

78.6 KB Created: 2021-06-12 23:13:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1f0c32d29697623d565f6eeedf41588f SHA-1: 330af7b52e2f3cb6d812a65b13ab215bee7b5292 SHA-256: 631a0cafae440c68e97e67e9e6d71ccac8e508016d40e6fd3876f9f31507a79f
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which are hosted on disposable domains and appear to be part of a link farm. One prominent URL, https://coretry.ru/pbw?utm_term=download+attack+on+titan+tactics+apk, suggests a lure for downloading a specific application. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://coretry.ru/pbw?utm_term=download+attack+on+titan+tactics+apk PDF link annotation
    • https://navijaxilof.weebly.com/uploads/1/3/2/6/132696044/siwasim.pdfIn PDF document text
    • https://malufatagu.weebly.com/uploads/1/3/0/8/130874424/wirasozadij-vemoporub.pdfIn PDF document text
    • https://pozebukewif.weebly.com/uploads/1/3/4/3/134330137/4027298.pdfIn PDF document text
    • https://zavomejuguz.weebly.com/uploads/1/3/1/1/131163615/1344637.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wiwedano.pbworks.com/w/file/fetch/144423987/albert_camus_veba_zeti.pdfIn PDF document text
    • http://zobifel.pbworks.com/f/how_to_use_starwind_v2v_converter.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/abe0691c-24cb-4387-bd33-bd0b4e461b12/how_to_get_free_builders_club_2021.pdfIn PDF document text
    • http://viluxese.pbworks.com/f/disolucion_diluida_concentrada_y_saturada.pdfIn PDF document text
    • http://vemebana.pbworks.com/w/file/fetch/144844878/how_to_make_a_paper_sailor_hat_out_of_newspaper.pdfIn PDF document text
    • http://gepefupugalu.pbworks.com/f/nclex_rn_4000_free_online.pdfIn PDF document text
    • http://garigor.pbworks.com/f/mary_did_u_know_pentatonix_lyrics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/058869c5-b0bb-4168-8838-08091388ea5e/rapajagikobovorumowo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e2ee7aeb-0e83-46be-af99-0c117ebfef6a/taranojidubigafifidurut.pdfIn PDF document text
    • http://fijovolumi.pbworks.com/w/file/fetch/145103571/wajanodobuwugovukugim.pdfIn PDF document text
    • http://mulasamesi.pbworks.com/f/age_of_empires_3_offline_installer.pdfIn PDF document text
    • http://winubuton.pbworks.com/w/file/fetch/145197294/watch_racing_tv_online_free.pdfIn PDF document text
    • http://vipagez.pbworks.com/f/51565534036.pdfIn PDF document text
    • http://kuxuraroj.pbworks.com/w/file/fetch/144728694/86529532420.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8b8401d-864d-4180-b390-706d001de9bb/ejemplo_de_dialogo_teatral_para_nios.pdfIn PDF document text
    • http://finebov.pbworks.com/f/how_to_build_a_deck_magic_the_gathering.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a9d67ebf-7843-4ff5-a29e-b68267155cf0/39595946172.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3d84932-a437-4a77-aeea-c1ceafb1146d/jijumadasuwevole.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/36ac7c2b-f949-41bc-ad06-13b7fe469705/32249162185.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7c189d2c-f1ad-44d5-a9af-616125bb6ffc/firefox_49_free_download_for_windows_7.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_off0000f5d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D2 5128 bytes
SHA-256: 597d0ecbdbcf0ed6ffe306832a60a26dd3845f270bd6debb27ac77802e455f31
font_01_sfnt_off00010773.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10773 10688 bytes
SHA-256: c6129aaa27713516c38b554cf32f99b70b8413a507c0579385d5b37b2c4ebb16