Malicious PDF — malware analysis report

Static analysis result for SHA-256 f86a55fc91155fbd…

MALICIOUS

PDF

77.4 KB Created: 2021-06-11 08:17:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: 146edbd84674b6246aa88f6e8383f2ca SHA-1: b13ea04bbb73d48ea6da5d87ce5316557e081e04 SHA-256: f86a55fc91155fbd8d230f52b8cb5c86404773f7c4605f406cab8684812a294f
156 Risk Score

Malware Insights

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

This PDF file is identified as malicious by multiple heuristics and an ML classifier, with ClamAV detecting it as a phishing trojan. It contains numerous links to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The embedded URLs and link farm structure indicate an attempt to lure users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laborke.ru/uplcv?utm_term=wordly+wise+3000+book+11+lesson+5+pdf PDF link annotation
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/ba5ea64k1nadfu16gfaee46u8o/zuwape.pdfIn PDF document text
    • https://rockdental.co.uk/wp-content/plugins/super-forms/uploads/php/files/21ae668924624de0eca6cfa4a3a8554e/suvedisiravenolilivir.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/0569d04f2a5248cac81fd54bfa77fe73/zorabodikufax.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/0328f589fe3dbc495e8658d3fe9e957c/95473128207.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/2d39dfbc141e97f8829bd4bf25a3adf1/labasofofuk.pdfIn PDF document text
    • http://seigyobannkaigaikikaku.com/ckfinder/userfiles/files/26079509190.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/f32bb7bfd77ca4947d0530310b3b8c43/62628142649.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160b754d634abf---81921953225.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/c46020c9484beae073ecda4e6c7793ca/50461490428.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/funuxojerekimowolixi.pdfIn PDF document text
    • http://dragonera.cn/admin/userfiles/file/dadasuzobulesawo.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160802fc225c9b---regofizexumu.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4084b7c9b---84827612204.pdfIn PDF document text
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/94bd6d967fd09788e8d8ea2ca4d78726/21673726789.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/2cecf9ced3972224ab81d4c743e75714/24583188975.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a384240dc9f---fudunotuvuvifefemex.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_off0000ebac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAC 5720 bytes
SHA-256: f5967ca8c4dba69be0e17f1f9cf0e28ae9b419d75f51d3d83d2bc2058c6ef165
font_01_sfnt_off0000ff5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF5A 11528 bytes
SHA-256: b7f3714157ba05e97a23cfc08e85acbf94da557cfe5e75e2a2e49269ed2520aa