Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9c3a0af09a8a86e…

MALICIOUS

PDF

80.4 KB Created: 2021-06-24 07:54:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 7d017c31a5f4c6a272833b11a89c35b6 SHA-1: c16740bdae9dbe56ee5ffe4f8227ad0a76f55cd7 SHA-256: e9c3a0af09a8a86e5260879f6f10986288648a6bd3e854c329e9d8c9e7b745a0
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/54a6e43d1e6263625d29731cd70520be/87412443619.pdf In PDF document text
    • http://szpk.hu/_user/file/32778324421.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/linogovoxonabigotiv.pdfIn PDF document text
    • http://eperon-kochersberg.com/img_db/luloliperijibase.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ab1d83acb63---mejegilinuvudimo.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16098bff5c12c5---29776725090.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/14238766363.pdfIn PDF document text
    • http://mwflower.com/upimagesfile/%5C/53350777204.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2666e9085---31825940107.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b50faa61571---wuletimapejojavadubam.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/67bb5a52778be5ac828caeace159b7b5/webosulibubasidujiwofax.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c1c09fc9c83---sujafimowiwabokorudofoxe.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608296bde73a8---nofire.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081311aef852---detixorexagamuv.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/DOqCt-cVA4I/uplcv?utm_term=casos+de+factorizacion+baldor+pdfPDF 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
    • 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_off0000de31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE31 5244 bytes
SHA-256: d38ebf82cc8e4a2a6aec6056070422a72c13b01cadeb4253638240c7adecffa2
font_01_sfnt_off0000f014.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF014 12720 bytes
SHA-256: d40beec7f96017e02fed3054e90c27cc6836837357dafd46e272ee7f825ba6ef
font_02_sfnt_off000119cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119CB 17036 bytes
SHA-256: 6b10e0b1903e892dc368153d6b7c520474c67db5a81cecbacabd7252ae5f34ad