Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd590bfcbd090657…

MALICIOUS

PDF

85.9 KB Created: 2021-10-13 21:53:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a8cd91a0df1e3f96bce2023c68d0a0c5 SHA-1: 456d3a5634045ff5676e03df8c1c7ecbd51956d6 SHA-256: cd590bfcbd09065758f316a4c8f8dfaf9e13b2c271e1cbf7e983666a7bd8e34d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://sklepbonus.pl/userfiles/file/witul.pdf In PDF document text
    • http://domesticsolutionsagency.com/userfiles/file/19521325605.pdfIn PDF document text
    • http://mrtowing.ca/Lawyers/userfiles/file/57978846081.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141c1eeea2d8---23074699554.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/2759596432.pdfIn PDF document text
    • http://safetyservicecenters.com/userfiles/file/selukamodiko.pdfIn PDF document text
    • https://karlholmbygg.se/UserFiles/files/27964751373.pdfIn PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/muzagefesu.pdfIn PDF document text
    • https://petribax.nl/userfiles/file/sulemawono.pdfIn PDF document text
    • http://gaudi.tw/upload/file/goligumofubozovi.pdfIn PDF document text
    • http://www.emploi.nat.tn/ckeditor/ckfinder/userfiles/files/20895489078.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16149c91489956---23641756798.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/tasizut.pdfIn PDF document text
    • https://pabxlg.com/userfiles/file/pilororegotosul.pdfIn PDF document text
    • https://cingenito.ca/upload/editor/file/53587962495.pdfIn PDF document text
    • http://fbrasil.com/userfiles/file///guxutup.pdfIn PDF document text
    • http://namadagaskare.ru/ckfinder/userfiles/files/16917382890.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/67294139465.pdfIn PDF document text
    • http://www.azurwelcomeservices.com/userfiles/file/80285984190.pdfIn PDF document text
    • https://nepaltravelsandtrekking.com/userfiles/file/rigedotosetigowox.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/4524fbe6517dadb6801aeb136e9a14ad/xirokeje.pdfIn PDF document text
    • https://www.serwkom.pl/plugins/ckfinder/userfiles/files/vumuwulokut.pdfIn PDF document text
    • http://zawodydrwali.pl/app/webroot/userfiles/file/pikefemiku.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/19010894921.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/RhDyTiV0TgQ/uplcv?utm_term=the+trouble+with+normal+pdfPDF 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_off0000e926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE926 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001013d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1013D 10884 bytes
SHA-256: 508abee8904f132849f806776464bb03f7f603c9d78609ceefce3fc97e4a93d0
font_02_sfnt_off000119fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119FE 18548 bytes
SHA-256: 0fc01a6d78cf3f0c69ba93953de649f3d54842b0b9d7f2f81363c6ff2aa0ea75