Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b3e77cb8b99256c…

MALICIOUS

PDF

76.5 KB Created: 2021-06-15 15:12:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: c161c2c38c47956253ae3f7f79298775 SHA-1: 0c64f88dbad1ad4bba76097cab0051f9e70bccb1 SHA-256: 3b3e77cb8b99256cf68dbda7270fd4d87e80d7bc56ae42829b1a7a436c2fd672
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF document that contains numerous external links, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing. The embedded links suggest the primary goal is to redirect users to malicious websites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://coretry.ru/uplcv?utm_term=barbara+ehrenreich+bright+sided+pdf PDF link annotation
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/17aej7atf2oaqua8nfeaqicjum/50188429793.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607d99f34c3bb---8214561668.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/1e2cf09197c620350c2f6c82f89105d0/nubawutixeluveku.pdfIn PDF document text
    • http://imi.vc/upload/files/xewukijijumaruzixesij.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a222b097dd9---87953981773.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/f3f39847fa3402f8c89981b79227832b/82667610789.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/56bh9a1pl2qibfu05mvgklaar5/waxikitozaxidifanu.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608b8dd01392a---turusu.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091e752bff6e---83382551743.pdfIn PDF document text
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/083050054b9dd1404ae574ff28fecad4/nadubasuv.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608944b869512---66058589684.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/3e6f816dbac0af5e2dca97084dfd45ad/74368748167.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070874ebba5d---77494213665.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/2381008309.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/tfhm9mb1bgqnd0rn3037ud21g3/nejemax.pdfIn PDF document text
    • http://alituncer.com/userfiles/file/29018621572.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB6B 5576 bytes
SHA-256: ea4dd5c92ca6b54b00686bd4d07ec046e530202a75df7611e9e3f5c56858b4c6
font_01_sfnt_off0000fe56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE56 11112 bytes
SHA-256: 36823583929cbb7a5a3ce0365e3ba462ebc4420f02c8313ced179698df181eed