Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f683e6625c5641d…

MALICIOUS

PDF

77.1 KB Created: 2021-06-07 18:32:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 3f8a0b48f0fcbc99959ecb77a03f0e85 SHA-1: 0c4a92c884e1343959d6bb2124b3366ae6d1a264 SHA-256: 3f683e6625c5641d841a634b8a566a4affda6720916d3627de13996b065dfcda
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and 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 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pistant.ru/uplcv?utm_term=libros+gratis+para+leer+en+internet+para+ninos+en+ingles PDF link annotation
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/g8gifkssvajhc6t9u6r55nptan/49797617100.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff5337380a---gobilan.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/sukubova.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b6adf4de57---66275618474.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/91855362864.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f242207db44f2c799e69782615c9d958/temewosobafobabolefovowub.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16093a78684421---fitujugimod.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/davasusowosukisif.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a908b5008af---pixisadadejawafara.pdfIn PDF document text
    • http://kwong-cheong.com/userfiles/ruxujukulukeririzipawilek.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/12d7b40185ae71ca9439ff9e3856412b/pesegepusiwoz.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9032b2bdf---kisorowud.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16091e7a3ef313---firabojubujubaxexaduvexuk.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d62a7a86ea---defebimepufupupos.pdfIn PDF document text
    • http://centronegozi.com/public/15386974645.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074ba0633f24---leziwavusopewivunitixa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000d837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD837 5068 bytes
SHA-256: 270a5066b87acde15a0d64ab09405e1522d8ad6529699d86cecb286116f50753
font_01_sfnt_off0000e980.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE980 11508 bytes
SHA-256: c78102498260818a559d0a3361522ef0f7bc59fb9c45e618344001b851f87625
font_02_sfnt_off00010f12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F12 16312 bytes
SHA-256: 531e37f64a2e7dc3bfb257675d9e6c644c7b1597f33ba9a969cd005a7ed65660