Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fdc0090f8027312…

MALICIOUS

PDF

78.0 KB Created: 2021-06-11 17:19:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 3473cd5aaf485083f541cd109628c621 SHA-1: 7cf6b68762808ba8ca1949dcdd6efd4368767979 SHA-256: 8fdc0090f802731283bff2ea701d4537d0b4d9931eabcdf44e4945853662a819
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, suggesting it is part of a link farm designed to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The document body, though heavily obfuscated, contains references to 'download human fall flat on android' and 'wkhtmltopdf', indicating a lure for a fake download.

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://catamma.ru/uplcv?utm_term=download+human+fall+flat+on+android PDF link annotation
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/p1vahmu4v1t62gjnta9amqtit0/kupakanawerenedixuf.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe7b76103c---japolilo.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16078ed912717c---kezupepimezobuburafaret.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/68b11af0f0875446886e07862704da8d/89411876258.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/d2be346e3bdb0dbb5d98d8991c8657b9/gugadamimopanemepukugul.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcfbe02e0b---26734540633.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a0cae304f73---jovaroxutebunorurafe.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021061109144473499.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/12371994784.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ad5459d3fd---65202923456.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0cd124c8f---foxavekurowowa.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/ce19c0f51a40fbc9a0890b5b56ebfc4e/3100040808.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071943833603---83165399036.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/59135116478.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b88ee82e37b---89515957353.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_off0000e7f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F0 5060 bytes
SHA-256: c9d4b1f66177b239cb565108b8de944ee3f8b260889b5202b682b23e37fd5af4
font_01_sfnt_off0000f914.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF914 22460 bytes
SHA-256: 13a9eadcac92c871069c1fdaa0e7c48fdd78a7eb1aa84ef8874112ea1cd1fe85