Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec689f5c85ef72a5…

MALICIOUS

PDF

78.5 KB Created: 2021-09-13 04:17:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f649f62da84235f7647390fed1df9e5f SHA-1: 8ed634d8211dc8b83b86ac41972a3095fc591e92 SHA-256: ec689f5c85ef72a5cc6f6dfb6612ef3e8ad6c0ad59af9adb2bfab510b49a0184
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 CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.caissedesecolesdu5eme.fr/backoffice/ckfinder/userfiles/files/46930639679.pdf In PDF document text
    • http://thanglong.vn-greenenergy.com/ckfinder/userfiles/files/96079692530.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/kasusigematol.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/bodokibunovuletufafo.pdfIn PDF document text
    • http://slovoveri.org/userfiles/19041002491.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613abbcf9357e---55475933819.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/88646514350.pdfIn PDF document text
    • http://charontrade.hu/data/file/62574935021.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/rodejunifiludidu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161342afe53c5c---lavuxeko.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/a065378881cca2a1bd795af12ce891f8/finiseditas.pdfIn PDF document text
    • https://nirmalujjwal.com/public/ckfinder/userfiles/files/71689101412.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/nedebamozagebuba.pdfIn PDF document text
    • http://studiosimonepantaleo.it/userfiles/files/34554205747.pdfIn PDF document text
    • https://indicaperu.com/userfiles/file/3613150221.pdfIn PDF document text
    • https://best-of-geldanlagen.de/userfiles/file/zatuwazazidadakuxil.pdfIn PDF document text
    • http://veitali.com/upload/files/nawazut.pdfIn PDF document text
    • https://signos.larrialdiak.es/files/galeria/files/82860671318.pdfIn PDF document text
    • https://cafepiolho.com/uploads/assets/pojirawotimetoxesewu.pdfIn PDF document text
    • http://dnepropress.net/files/file/38828154625.pdfIn PDF document text
    • https://ikomsolutions.com/admin/userfiles/file/13857806457.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=heat+capacity+of+h2so4PDF 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_off0000ca87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA87 10632 bytes
SHA-256: 9039eb81617fe3352e265ca03d00470b201add604d2c8aa9c5292edc8bef2087
font_01_sfnt_off0000e317.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE317 18596 bytes
SHA-256: 9cc59650503ebb651a0314edd32775d2c0bc9c0a7dd7d446238e959518230172
font_02_sfnt_off00011376.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11376 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1