Malicious PDF — malware analysis report

Static analysis result for SHA-256 d309a859c92e673d…

MALICIOUS

PDF

88.5 KB Created: 2021-06-12 19:20:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 3b19b05a6fdb4167865563a09fcee05c SHA-1: 8fe038351f5b1ba366aa7eca2976f2a6bc600c73 SHA-256: d309a859c92e673d24ab621f57f15343edd33a781b920cc9e20911b3d012cdd6
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous external URIs, many pointing to compromised CMS upload directories, suggesting it functions as a link farm to distribute malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://oniceh.ru/uplcv?utm_term=alif+writing+practice PDF link annotation
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607707af96119---62423054820.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b8cee1bb99d---zidofagunumaxatefodofum.pdfIn PDF document text
    • https://asset-books.com/userfiles/file/40098822418.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/dbjsnclh0ufm2a8jrlsjkoeef6/razisefuzuluzavizedataz.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160820b28c8932---94690644021.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/62aa41523c9c4604638293ad0feaf6da/zituxenozexenifanuboxufe.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/55a0b9e1aebc5d81a68854d53ee7fc1a/rolipewelo.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/d579f45b51078a9d26fbe9aad2f26dc4/fapevoxopanomir.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/bd01phj3mccis72m5u529adar2/96454986531.pdfIn PDF document text
    • http://hasyo.net/files/file/62232861008.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090cfbcc53df---57389783491.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/e06ef59b315350ba2585ecc95061b4a6/zonidero.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb8097afb4---72730182129.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ab74e75c434---99293416869.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/n6vaf7takq5qjg8mfdnr3de3h4/13722071124.pdfIn PDF document text
    • http://arabicquick.com/content/uploads/In 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off000129c9.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x129C9 24740 bytes
SHA-256: bd7c0e2278bb9e87d328afaffa260f62363a6f2e2b70de1ffc965f4a3ea1fcfb
font_00_sfnt_off0000f252.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF252 5088 bytes
SHA-256: 3c9739f9b766f0e33a8789c10cde047bf7f064b66b6efcff39ef177d47c37f95
font_01_sfnt_off000103ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103CA 11088 bytes
SHA-256: 87788c24775364a8f60d0b86e5d8fb32515a17571b567800eb00629543ded40f