Malicious PDF — malware analysis report

Static analysis result for SHA-256 b829d839dc64cfc7…

MALICIOUS

PDF

73.3 KB Created: 2021-06-18 06:34:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 5ad0336136fbc712a45852570fc19a75 SHA-1: 2d67be6412b04d34a03fe2f1e01e5a8a896b1774 SHA-256: b829d839dc64cfc7dd31bf4fb40d880239f1b96bd366d7565831a99757e6b13b
156 Risk Score

Malware Insights

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

The PDF contains numerous links to disposable hosting sites and compromised WordPress uploads, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via embedded URLs. No scripts were extracted from this sample, but the structure and URL patterns are indicative of a common PDF-based phishing lure.

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://smidgel.ru/uplcv?utm_term=capital+letter+handwriting+practice PDF link annotation
    • https://alkirbilaw.com/userfiles/files/57594274117.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bda22e3d8c---latakakaranip.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/c230832f90612ef78b1a90d80c2d2e6a/ruvonesekutadume.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/91716625310.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/bbd7247dff77ee9bfd97d2cc5730d3e0/zerewuke.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16098ef36e76ea---nuzetofakalulonavaj.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a008b8ff2---sefunukipazokiwof.pdfIn PDF document text
    • https://hasekei.jp/userfiles/file/68733567796.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607837ea1f5cf---pixazuxividiwabemafomupa.pdfIn PDF document text
    • http://dent-pro.cz/pic/file/repativilevonowivagefib.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090a0ad8cac5---watuxunuzanewedo.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/r08850gau9jn4mvrdpnt4509n6/50376446827.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/86046212590.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f6e4f2d95---terawatuteneta.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/5145435e8d5236c36b9644f7489d9192/82922049142.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa1af5f04d---92979891134.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3AE 4952 bytes
SHA-256: 7f64064b2ba2129234dc89591b57ec5916e3349549c345380d4c44ddb6143bf2
font_01_sfnt_off0000e48f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE48F 11116 bytes
SHA-256: 8a5c70746a2ac9192165cbc7fca15feeb93c2709fc4fa339ae447cbd7f48f84f
font_02_sfnt_off00010a52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A52 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361