Malicious PDF — malware analysis report

Static analysis result for SHA-256 f57d6c0d36b86161…

MALICIOUS

PDF

72.0 KB Created: 2021-05-29 23:13:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 163521141035a70252c4348e39441fb2 SHA-1: cb1a612672b3f440f92551bfa23adb5ddee9d769 SHA-256: f57d6c0d36b86161c468c07aea65cb10b497b3df5c6146e5d3e050f84048ebbc
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting it is part of a link farm designed to distribute malicious content. The embedded URLs and the nature of the heuristics indicate a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://chcial.ru/uplcv?utm_term=heartstopper+alice+oseman+pdf+espa%25C3%25B1ol PDF link annotation
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16097aec20c500---rilimonituga.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16099f0c1768c6---zoxafa.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/ke6joarg5u3il9805i506pfi35/fuxidamojo.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb7de40109---nuxudujabogeg.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160a20c0d8d76c---zigewovojikiro.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7d6ba7d25---13615429369.pdfIn PDF document text
    • https://bistakalikotenetwork.com/userfiles/file/wekubapokamigodobi.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9e0196970f---zedegupusuwisuxugowurum.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607812bc1d951---89718865212.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/f27b9a4065d7e834654bfd4a4a38b936/sogutes.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/ba1cd4eee0699252422bba1bac6c450b/rozudunefuxebulinanu.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea0f89e4eb---35131525575.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160a8738e2c630---wejekipatanukododewe.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/ee407s4ofh35677ercq0mjnla2/bejefuruvaseb.pdfIn PDF document text
    • https://bleikss.com/userfiles/file/kekasowuwav.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_off0000d87e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87E 5476 bytes
SHA-256: 4d4a090365c72efd38f12c8050fe4f16f31dad5efe47ca04d17c34de945e2ce5
font_01_sfnt_off0000eaca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEACA 11604 bytes
SHA-256: 8620e6cb558369479ec8559990ce5f72b2534b271d7f904538d8483fd2ed77d5