Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d587c4fd91c746d…

MALICIOUS

PDF

84.4 KB Created: 2021-09-18 00:28:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f90a9d2b56919ccf48d51b299de3eca1 SHA-1: 3c431450d8d7b20415a9e266ab64df8bb3f047ff SHA-256: 8d587c4fd91c746dc713c5f541cbfb221e80ea402fa1ac8262115e7cbb82cdaa
66 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to disposable domains, indicating a link farm designed to obscure the true destination. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the structure and numerous external links suggest an attempt to lure users to malicious sites, potentially for phishing or malware delivery, aligning with Spearphishing Attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 4

  • 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://ms2oke.com/contents/files/ketevopugufawotaxeb.pdf In PDF document text
    • http://gurolmumcu.com/userfiles/file/delife.pdfIn PDF document text
    • http://euro520.net/userfiles/file/1631465653663919215.pdfIn PDF document text
    • https://mallarpurnaisuva.org/go/file/sivuluwuretozokiwesasoj.pdfIn PDF document text
    • http://sichera.eu/userfiles/files/13434483161.pdfIn PDF document text
    • http://meubelenindex.nl/images/uploads/97840437015.pdfIn PDF document text
    • http://homeopathyhongkong.cn/files/waropuzakapisububurur.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16131916c62e8a---moxuzenawono.pdfIn PDF document text
    • https://gmnavarra.es/ckeditor/files/suxinibijax.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/jemarosadigolelufixif.pdfIn PDF document text
    • http://okna-kursk.ru/page_edit/_samples/userfiles/files/46101322257.pdfIn PDF document text
    • http://rigdrilling.org/userfiles/file/tegofevetabisupanimaze.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/36568549301.pdfIn PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/69965592434.pdfIn PDF document text
    • http://linkingpeople.info/userfiles/file/duwiwi.pdfIn PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/22294972864.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210915224128.pdfIn PDF document text
    • https://inoxquochoang.com/app/webroot/files/images/pages/files/75273518932.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fdbb459f81---nevewenubabekedosan.pdfIn PDF document text
    • http://jmvlpslimited.com/ci/userfiles/files/kigurag.pdfIn PDF document text
    • https://hamzsabegi60szallo.hu/UserFiles/File/nalitinibasasi.pdfIn PDF document text
    • http://szpk.hu/_user/file/kefaweberilawivimumuvu.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/rerejamidozan.pdfIn PDF document text
    • http://soles2walk.com/data/file/weganurovetopujekokuju.pdfIn PDF document text
    • https://rendszergazda-cegeknek.hu/ckfinder/userfiles/files/61032577654.pdfIn PDF document text
    • https://youkuvpn.com/upload/files/30772562442.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=the+official+sat+study+guide+2021+edition+pdf+free+downloadPDF 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_off0000e0c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C1 18152 bytes
SHA-256: 6fec6bfbfc4ab556700edd40a590d72f0a99e240165d66635c68b92caef7bf23
font_01_sfnt_off00010fce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127E5 11456 bytes
SHA-256: e1615cb47878e02bf9d8b806f3dcba5ff9862affec2ca7b5ab9d3429bf4ef4ef