Malicious PDF — malware analysis report

Static analysis result for SHA-256 a660dd92799114f7…

MALICIOUS

PDF

76.4 KB Created: 2021-07-23 23:42:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 8581a0aeed3e90eb4e0444f8f0a66f1c SHA-1: 67bd7f44a63f7eedd90a13fe5137eb19bc22a736 SHA-256: a660dd92799114f77a87c76829c3f0530384ca11d21839be4e59311d0970db90
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. The ML classifier strongly indicates maliciousness. The primary attack pattern observed is the use of these links to redirect users to potentially malicious content or phishing sites, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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://pnlcoach.com/misc2/file/ In PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/p2sbni0refbi0fvvom64gjjsr7/sowazinewatanatoxeditibu.pdfIn PDF document text
    • https://togeltop.net/contents//files/6625029662.pdfIn PDF document text
    • https://amitadevnani.com/userfiles/file/zakesibejimevekituk.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077a6a472a48---4983870106.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/a79d8252ede34ed73d262e7be9087f74/43203945279.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f95d3ba4dc---negevegigazujalozafev.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/q7iile4qdgd3mbtd6hf76r6ul7/12705698750.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/8ceeef7fa4ceaa06cbaff799208b7845/11698329020.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160891483ed7f2---30628016186.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/c4c62bb025ed292b2831672ef2a1cf91/95213736707.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/10191903546.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/2gv8ilsum95ed5il0ed9lnb9g7/kivesapu.pdfIn PDF document text
    • http://thaoduocvn.com/userfiles/image/file/86518739867.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcd2132fef---58041977798.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/98981982673.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/h2rnggkm52eoqmco2g9b37jmuj/12066325960.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1ed92427d---jitapuji.pdfIn PDF document text
    • http://hutbephottaihaiphong24h.com/upload/files/fepovegod.pdfIn PDF document text
    • http://joyearland.com/ckfinder/userfiles/files/5570836530.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adfaa3d4002---10815845237.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bbc6e548099---52172017899.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=geometry+for+enjoyment+and+challenge+new+edition+answersPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c71d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC71D 15988 bytes
SHA-256: 49512f5dd140e616adf1557a30cc2411df3351cc797e2769e239d8464ea2a37b
font_01_sfnt_off0000f06a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF06A 11292 bytes
SHA-256: 9f06f034b498ff70f7b8de44e04457c5a38c862d9ac64d4f3d4789a1115aa8e8
font_02_sfnt_off00010a9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1