Malicious PDF — malware analysis report

Static analysis result for SHA-256 b334df90eebd28bc…

MALICIOUS

PDF

90.6 KB Created: 2021-09-02 10:12:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: cacdb7d0b67925c011af18c65cb99d47 SHA-1: 756cce01c9b9489236bfc6f3e4c58c24444386b2 SHA-256: b334df90eebd28bcc44387cf4f4d8be6feba5d99ec9c06cc56f0c731cd2f907f
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609658add85a1---1052332942.pdf In PDF document text
    • https://pet-fashion.ro/mm/file/7442085473.pdfIn PDF document text
    • http://www.conectadoscomdeus.tv/arquivos/file/juvopafez.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/legapepuleletibapivib.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/fegaluxobusoguriwab.pdfIn PDF document text
    • https://hosvagyok.hu/userfiles/file/bumamopuxapefabis.pdfIn PDF document text
    • http://learnazia.com/fck/imagesfile/99941225435.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/af8d7ae20c0bcea6b05490ddcf3b1b8f/kizukajevimuxewafimov.pdfIn PDF document text
    • http://hiddenforrest.net/clients/76790/File/bixaduzasisepokow.pdfIn PDF document text
    • https://mosallaesf.ir/uploads/ck/files/nesamefevirukumep.pdfIn PDF document text
    • http://okwmd.com/upload/fckeditor/file/11000844083.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/bijutenoxonexumorakuge.pdfIn PDF document text
    • https://livre-d-art.com/ckfinder/userfiles/files/73229227085.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/pagibobak.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b44571cfc50---99804322423.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/nulefifofabuzafusukapadix.pdfIn PDF document text
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/lhegfdvutc5urph76tekr7vjms/13780775669.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/gufifugiximepetolo.pdfIn PDF document text
    • http://maxtarget.by/ckfinder/userfiles/files/bokusupajutises.pdfIn PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/60853034004.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/tujikasetexafe.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/04af5f9e739bcc7f6c48338c939e5b98/31292163989.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c887795b228---tezejubugasi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=construction+wbs+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_off0000faa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA4 18956 bytes
SHA-256: a280dcced01ba2d720dbe0bee5323cec85a51ace51efd6158e961a05b0b1d0cb
font_01_sfnt_off00012b8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B8B 10992 bytes
SHA-256: a4502bd9b29c9179a1054b2f24d65cf44931bcd4ae35abc9eeb0d19f4851e5a7
font_02_sfnt_off00014506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14506 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1