Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c94b233ab503c2b…

MALICIOUS

PDF

81.3 KB Created: 2021-09-19 20:17:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5e0abe05f0fa532ea027a24e2ab79eed SHA-1: ed9dd0634079d009922a7e275cadd25adfb4820f SHA-256: 4c94b233ab503c2bf6cda5e7a98b4f4a4f743ecf906e1cdf0f1f2941ce2ab090
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nomylo.ru/uplcv?utm_term=game+devil+may+cry+untuk+android PDF link annotation
    • http://friend5190.xyz/js/ckfinder/userfiles/files/51270694211.pdfIn PDF document text
    • https://www.luxboss.com/ckfinder/userfiles/files/gobaxejudubipibazez.pdfIn PDF document text
    • http://navrattan.co/userfiles/file/36262933711.pdfIn PDF document text
    • http://naitikfashions.com/ckfinder/userfiles/files/63739122335.pdfIn PDF document text
    • http://honghuibio.com/d/files/44088455428.pdfIn PDF document text
    • http://fillaracingacademy.cz/ckfinder/userfiles/files/73132460025.pdfIn PDF document text
    • http://upservice.expert/admin/ckfinder/userfiles/files/50592494736.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/28009767124.pdfIn PDF document text
    • http://canhtoanland.com/upload/files/kakojefizezizelotavo.pdfIn PDF document text
    • http://a-pluset.com/userfiles/40589390692.pdfIn PDF document text
    • https://rcot.org/userfiles/file/gemotugu.pdfIn PDF document text
    • https://haciendaloscipreses.cl/upload/file/woxesokirav.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3103e5631---46797753855.pdfIn PDF document text
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/70186689001.pdfIn PDF document text
    • http://dasbluemchen.com/rolatukuwari.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145e183469ec---21713155963.pdfIn PDF document text
    • http://www.its-dph.cz/admin/fckeditor/editor/userfiles/file/naduvi.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/mejerovakobuwijudusake.pdfIn PDF document text
    • https://ghnservizi.com/file/43138361108.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/161367fe361ab0---wurewonubeguporumudonug.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/45363382736.pdfIn PDF document text
    • http://purofirstli.net/userfiles/file/sasusomusovudu.pdfIn PDF document text
    • http://drumlockingclamp.com/FCK_Editor_Images/files/76333627478.pdfIn 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://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_off0000d6b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eecb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEECB 10776 bytes
SHA-256: 6dd68014ff31dd805c57a2148fd00a5d3eed245b94df0513ee803d36678182e2
font_02_sfnt_off00010791.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10791 18520 bytes
SHA-256: 44bd9ab6231425ebd64b7ee1e3aed0c1a654f817ecf545ceaf17143bfa78edaf