Malicious PDF — malware analysis report

Static analysis result for SHA-256 686a240f84a9c215…

MALICIOUS

PDF

70.4 KB Created: 2021-09-17 00:10:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6dbebd04e2379f8129e825504b577a94 SHA-1: 2b2f49414b91c062111d6729e09a6cb74e507340 SHA-256: 686a240f84a9c215b4e3d940c471d2274f7f1fc3bcf4a0ee2eb3777414e35d46
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. The file likely serves as a lure to distribute malicious content or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://drafthe.ru/uplcv?utm_term=talking+tom+bubble+shooter+apk PDF link annotation
    • http://chinhsuasolieu.com/media/files/6747728237.pdfIn PDF document text
    • https://bacninhonline.com/webroot/img/files/sekikebebuje.pdfIn PDF document text
    • http://leasingtowers.com/ckfinder/userfiles/files/vofulo.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/f5d1a8f564e9ecbb2fb36d3ca1f0157d/83417568105.pdfIn PDF document text
    • http://plncse.hu/php_data/file/wowavadipikulizexojam.pdfIn PDF document text
    • https://valenciamaids.com/userfiles/files/39263958129.pdfIn PDF document text
    • http://cafehinglung.com/uploads/files/vulopuk.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/542628728.pdfIn PDF document text
    • https://skywaytravelandholidays.com/ckfinder/userfiles/files/xevubaf.pdfIn PDF document text
    • http://xn--hh0b97d8is16e.com/userData/board/file/gofolefuwafekuwipibapel.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/96777422692.pdfIn PDF document text
    • https://mtmhomeschool4art.com/mycms/uploadedimages/editorUploadedImages/file/97497455051.pdfIn PDF document text
    • http://bdsductri.com/upload/files/44426671738.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/16132079a36dee---wofozanapuvadunaresuton.pdfIn PDF document text
    • https://paperland.bg/uploads/file/62741472171.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/tajusatanutujunoruvipifan.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16137fbdec85ad---11697962332.pdfIn PDF document text
    • https://dongphuchuytai.com/upload/files/14861232197.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/kelusupisawitezasix.pdfIn PDF document text
    • http://ros.by/ckfinder/userfiles/files/gusogolukigexol.pdfIn PDF document text
    • http://riversedgefm.com/files/file/tewepuzad.pdfIn PDF document text
    • https://millvalley.com/wysiwygfiles/file/64699887743.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/73726585416.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://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_off0000b427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB427 15452 bytes
SHA-256: 993e7f7c7f34ad07df4aab27e7d7ef955b9b4aa44be5c2e27c7ce0654320a74f
font_01_sfnt_off0000db24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB24 10992 bytes
SHA-256: 6cf7de173f6b7c122d9b6cd0f2a10e7579255444a7b9a63a7a741b87f10a4797
font_02_sfnt_off0000f44a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF44A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1