Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f2436ab9043ec76…

MALICIOUS

PDF

87.5 KB Created: 2021-06-21 05:55:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 671a346beb57f2d932467ee5cf949174 SHA-1: a824400377d865f4fd065626f38a594e04b033c9 SHA-256: 5f2436ab9043ec764756380b42b3211057172a06ae3f4ac77e5b589b2abecc4c
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to PDF files hosted on what appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for SEO poisoning or to distribute further malware. While no scripts were explicitly extracted, the PDF structure and link farm heuristic suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd8b2cc62c---17889284596.pdf In PDF document text
    • https://btsmstlucia.com/atomicsteps/upload/userfiles/file/70540280052.pdfIn PDF document text
    • http://verynailscm.com/user_img/file/nifipav.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ae6d613d625---buxebirufomuwudelekif.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/06701c5a63e6d5646d1edf6fcf912a8b/43760966856.pdfIn PDF document text
    • http://www.adarshvidhyasankul.org/userfilesfile/zifapokijuw.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8fe23595ca---9198805215.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/3110ccad289cd589babaff409d5d6b06/11194961092.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/99832301689.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608beb71559e3---nuteni.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/4730440695.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160945ba8499f5---wekibulinakovowunova.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/0l3q9t9l9s9jrd4d1nq24uf5ls/14992642258.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/36brg5eccdvqvhmd1brjkga7lp/konam.pdfIn PDF document text
    • http://controldellaves.com/app/webroot/arxius/file/kakowivoz.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/86449095031.pdfIn PDF document text
    • http://seamacros.com/upload/file/75568687717.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/29062432133.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=farming+th+11PDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000117cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117CD 4896 bytes
SHA-256: b9fc05f6e8c6c2be2fe7cf68bb6449830982abbc1a203a47284ca272f88293a1
font_01_sfnt_off00012854.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12854 12192 bytes
SHA-256: dda474bb2117e3531e5a7dd5e7f131636ae67b6a27720300044b84356145c18a