Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee21d345e2cf2900…

MALICIOUS

PDF

105.3 KB Created: 2021-09-03 12:58:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 37ddd8849bb4c5365bc238c10f5ae4da SHA-1: 9c57173fad9e491cba3a3899f1fbc40283add265 SHA-256: ee21d345e2cf29003a9424c3bd5f2f50f848b0759798ef87fe64a6bcccc74cd0
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites and disposable hosting, suggesting an attempt to distribute malicious content or manipulate search engine results. The ML classifier strongly indicated maliciousness, and the structure aligns with techniques used to host secondary payloads or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071fb5675c36---winemarosami.pdf In PDF document text
    • https://calienglish.com/ckfinder/images_store/files/34959483185.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/34322753689.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/88558012064.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/hle5vfphmd5eff2j791p8qkhp0/filalivunisetokakutode.pdfIn PDF document text
    • https://fetogram.com/images/upload/files/regifobodesivoxolovu.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/saril.pdfIn PDF document text
    • http://siamintertrade.com/file_media/file_image/file/64192422532.pdfIn PDF document text
    • https://thietkewebseo.com/webroot/img/files/mowusewumorekifoseso.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/9o1qtcren1j47oeup47a2h68g6/susekezolelozud.pdfIn PDF document text
    • https://alajuusa.ee/media/contents/file/mufasikunupaxowemisin.pdfIn PDF document text
    • https://scalper.ir/data/files/file/58635715161.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/sanadesagovipunumo.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/panowifej.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcbed835e12---duzowozuvetazuvazolemagi.pdfIn PDF document text
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/3ece8dea1defba7c16ac30784cb79087/37473592038.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/f365ff2bac62a8ed5d036c5413bfcbe4/21910523189.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/32729232492.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1610344e295562---tufuz.pdfIn PDF document text
    • https://j26clean.com/upload/files/93122219430.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/dfdd0cf7ba72eb81527da8e8f16a5e51/redumorefevabapakamusani.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/f6ff5f6bc9547db47489900176577ef8/mafuremunajizavigupobad.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/puwibulir.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/33610222136.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160b993931f802---goluxoxojunopupakiwe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=introducing+yourself+in+german+worksheetPDF 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_off00012f88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F88 20192 bytes
SHA-256: 72704af27e17c82fa7d59d658064fee971270744b5204aa8abdde5761d637eee
font_01_sfnt_off00016519.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16519 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00017d30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D30 11268 bytes
SHA-256: 3fa425702f4b13cb33f038cb9c340976a9448ab7deaf3f8286a81bab7eb9b17e