Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c3f430ec4ca2938…

MALICIOUS

PDF

76.9 KB Created: 2021-06-13 22:05:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: b4d1bdae79e6879b8dd143faa0139b3b SHA-1: fc225f723e6cd02d8f0482236fecd3e43fc515e8 SHA-256: 7c3f430ec4ca293820de0a3b7a11ebda8f8bbb285e275ed7190460f082ddc401
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a deliberate attempt to obscure the final destination and potentially engage in SEO poisoning to lure victims. No scripts were extracted, but the overall structure and URL patterns are consistent with phishing or malware distribution campaigns.

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://crysiq.ru/uplcv?utm_term=english+as+a+skill+subject+pdf PDF link annotation
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609247d65cfd0---suzifuzivapivurufo.pdfIn PDF document text
    • https://kildevangen.dk/files/72723060815.pdfIn PDF document text
    • http://tamilannuaire.com/var/www/vhosts/vps296430.ovh.net/tamilannuaire.com/images/file/vureselunovo.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/16094223ca610b---vepaduza.pdfIn PDF document text
    • https://menu2uplus.com/images/file/87551563403.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d442ce3b09---61600787346.pdfIn PDF document text
    • http://zoncmswebsitebeheer.nl/files/editor/file/jatedexaxijiwudo.pdfIn PDF document text
    • https://egca.fr/userfiles/file/fuzopavutuzi.pdfIn PDF document text
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/68369361287.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/7v0tgek92rcf2aj1jdven9fla7/40582192928.pdfIn PDF document text
    • http://soupworld.de/upload/file/88943858840.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/28edb84b2a0b37a9ded03c9520988647/48596326251.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/k43veq7d09ipvhgvh1qsh1ukr1/36931691319.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/88e470c3795030dace5e7e260d2e24c5/nibiduwanowelifezijevus.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160707edd45182---76713001663.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_off0000effb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFB 5560 bytes
SHA-256: 1e179ffd5094cb2fb9884316f0253453abb746406f264166c6014886a504cb47
font_01_sfnt_off000102eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102EB 10464 bytes
SHA-256: f2e50964ad30383247892fb266838042a6def5f20ffe95e7877d990c7588c7ec