Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca26791921aec7f8…

MALICIOUS

PDF

87.2 KB Created: 2021-07-18 01:54:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 3bde6ba50656d61dde0414bebc9d7cca SHA-1: 08da9d6d07eb8ed9bab65f0c2df36c10e0bfdda6 SHA-256: ca26791921aec7f8108cad5dacce4702b48a8077b34bdf0214e2ec0bb9cc037c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised or disposable domains, likely intended to lead users to malicious content. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://artstudiodesign.it/userfiles/files/92694184463.pdf In PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/4bf3g1ordjn94clf7oq60t4ivf/poxobiwifen.pdfIn PDF document text
    • https://baptistfriends.org/media/62387569423.pdfIn PDF document text
    • http://cassotech.nl/site/data/ws/files/fexubuzoninali.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7503e6ebc8---16751935442.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/10bf66dc9f81bd33a5f5c48998a1b5db/11174379952.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608d86899b6c1---telaj.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/vgqun9ptsjo977q3u508r15f6d/19270079343.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/785aceb7b46b2a0d90c9c495695c9741/88948563295.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ac67dacae29---golategin.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/42310402114.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/qg2h08v68ge9os1ei7ilqd6sai/71149070144.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ab2b6c09830---15740909164.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/xanosuwanava.pdfIn PDF document text
    • http://josephlillianmorrisfamily.com/clients/59960/File/42867821548.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/1ammrkavo86g702po5nekm9mn1/47045681613.pdfIn PDF document text
    • http://michelesherrinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/72694952686.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=things+to+do+with+paint+samplesPDF 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_off0000f2a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010aba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ABA 17036 bytes
SHA-256: 00b51a95b57d230a9cb1e6fe0de4736e9178d97c4dbddf96bb2b73c5d0962196
font_02_sfnt_off00013764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13764 10788 bytes
SHA-256: 37ea80b493eddac1bea1e7eed9730ffc1e5f348033e8f16f62f8634248260da9