Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1f7033e7f16f4ca…

MALICIOUS

PDF

84.4 KB Created: 2021-08-17 14:41:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0f2a079bc596724703481e797ef9d40e SHA-1: 759a86539e853f38b19685e54f630e1d1605067f SHA-256: b1f7033e7f16f4ca892c3451dc82e2e1e6caa3ca73800689b66f2fec4e3d5ae7
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to other PDF files hosted on various domains, many of which appear to be compromised CMS uploads. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to manipulate search engine results or distribute further malicious content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://www.vikingmaterials.com/img/83477203110.pdf In PDF document text
    • https://namphuctourist.com/userfiles/file/dizukoxedoveziwejisapa.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/15c77b34632d9bc3440559f9e80e6770/bogipigurolofovapejelad.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6794d0cfd2---buzawuside.pdfIn PDF document text
    • http://flambotour.it/themes/userfiles//files/4202070419.pdfIn PDF document text
    • http://wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/80445511887.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/rhilbvcjkt985aq5fdaktgql9j/nususeripavukevotiniso.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210529_144324.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/wewexakikilo.pdfIn PDF document text
    • http://gerastar.com/userfiles/file/jazemakasufuxubelemapebez.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d91d7e79ff4---faxetonesegifurilabipim.pdfIn PDF document text
    • http://yoron.net/up/files/nepimedimake.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16074b8672f9b6---55220247986.pdfIn PDF document text
    • http://flirdining.com/uploads/files/zebubudizigawitisi.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/lupuwojezobifomugezikof.pdfIn PDF document text
    • https://evpersoneli.net/ev-personeli/file/62853343712.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/movatoponumevekimimilime.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5fe6383ea---4887782672.pdfIn PDF document text
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/bonuwefixijixapututilesa.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf504103ce---potonawijor.pdfIn PDF document text
    • http://batiment-tunisie.com/userfiles/file/65173914774.pdfIn PDF document text
    • http://ecilingirler.com/resimler/files/98203363092.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1609d7090b176a---fivezike.pdfIn PDF document text
    • https://motacademy.it/file/bejujinaki.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/japexexe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=what+is+the+basic+accounting+equation+explain+with+examplePDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e2b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B9 11288 bytes
SHA-256: e3d95e2b054559caffa7bdaa1026d18c0fe41a58a1bc289ee1f1b86afe88f7a8
font_01_sfnt_off0000fc9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000114b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114B1 17624 bytes
SHA-256: f9101a39e73b48b9a00181e672c31b2ac649c5f07890b30da9096c5e6887c69c