Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf5cee5254c97cac…

MALICIOUS

PDF

88.9 KB Created: 2021-07-03 10:26:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d398554a7d154e94a7f7e9b0bc94172a SHA-1: 404a08bfb72a0e3e15f06a8f20a2b547ecc7994f SHA-256: cf5cee5254c97cac77a756c35c24d8a00db6fa32ea6760e16cf7b45e99dc447b
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised CMS uploads and disposable hosting domains, likely for phishing or SEO abuse. The embedded URLs and the PDF structure suggest an attempt to exploit user trust or search engine algorithms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://condominiobrisasdelnorte.com/userfiles/file/88657411660.pdf In PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/05051803cd39913c68bdfad4d535f650/65706415850.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/46701123989.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/59nkpq0jc6aacq9ao7hm7m0507/geponebikaguli.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/1e6a8efd2e25da72eacec6c32f7c64da/56228494567.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ba50164c957---kemasipodagebusibugix.pdfIn PDF document text
    • http://xn----8sbaqfskngn1qi.xn--p1ai/userfiles/file/juvuwubisedizenezowesex.pdfIn PDF document text
    • http://bachova-terapia.sk/images/file/61085943051.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/xazivaler.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16086115db14b3---surijiwibadukit.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/67743322840.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077a1da0185c---fosada.pdfIn PDF document text
    • https://underworldgear.com/upload/users/files/58539609229.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/1b9a81ff37868d9653e0f2b6862e4b2e/64657992520.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/gexoxorunugozamarexabuxix.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/0l6rh5qjmded7m75m74valt5in/12855789125.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/8cs44s4fdi7kcdmln8avs0fsqc/21703228841.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/eftu14acoqotvp7badtquv5r10/17051454187.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/0bbfb1c556df0e628924ca532f823a9d/44345187789.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/f9a1cd36480ecf17ce5c54d61fa4ad2d/59655893895.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160946a69aef94---71695542564.pdfIn PDF document text
    • https://avela.md/userfiles/file/makor.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca6c65c725---12603680780.pdfIn PDF document text
    • http://jan-fotografie.nl/upload/files/pizuvujobekiku.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1608007d99ac73---paduvipojafenikipuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=chiricahua+national+monument+entrance+feePDF 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_off0000f91e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF91E 10564 bytes
SHA-256: 96ab0051796c4a17cbc2f44a4c61942a42a89d15ad8ddae41831e250fe53f857
font_01_sfnt_off0001110a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1110A 17112 bytes
SHA-256: 44787627a241f6451c70dfbd7c13b706f51b74a08b19ccad825274fc5b5c3f76
font_02_sfnt_off00013d55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D55 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1