Malicious PDF — malware analysis report

Static analysis result for SHA-256 87b9de6b4bf912af…

MALICIOUS

PDF

79.3 KB Created: 2021-05-10 01:17:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 01c095769e9c322734275f30a033df2c SHA-1: e10691c23c891b68af7dd8c43a652b5b153bfe7f SHA-256: 87b9de6b4bf912afea8b0a9cf8f7617a82419794687cd690b192c05049c8e35f
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm or phishing attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to redirect users to malicious sites for further exploitation.

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 http://etcad.net/np/upfile/file/31649806958.pdf In PDF document text
    • http://alarcon-v.com/editor_upload_image/file/gerotazub.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/nikemejuxarevufurot.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/85b9c3065ceecbe731208448c83c3495/limodigu.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16071a1e62f454---sixux.pdfIn PDF document text
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/69722023db1d75b0e01ebd2ec90fc5ae/lupovigimigarugogufakeme.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1607d21a0b84ad---wawusotovisajubuzifutekim.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/g504ahdaqpvo4760u37b7p8l7d/51654949518.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/8728d781221b464c7840f04969ebd744/zulir.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/4030c0424e9398260adbf1bb1684665f/meretote.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/03008a19aaad50f6ffd13c537c8e4a98/marazesujenoguxigi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9919e6995---juteboxijonavesewe.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160851645c8635---sifidowenoponoxilewunu.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/72f8b6c5a407c4d82a2f11facad00a8d/tinel.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16087ac18d33af---56662476569.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/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=seat+ateca+cupra+performancePDF 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_off0000fa2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA2E 5056 bytes
SHA-256: 7cd6124a73eafad53f9ad42001d5ab00d208e7e647c29ea0f7974c1a5653bb3e
font_01_sfnt_off00010b51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B51 11024 bytes
SHA-256: 64ba81ca5b09f8e46a6a3ceab82fa5a9891287ded1e22994be003571bfd7f4f1