Malicious PDF — malware analysis report

Static analysis result for SHA-256 51fea3b9a384299b…

MALICIOUS

PDF

79.2 KB Created: 2021-06-17 23:20:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: da1f783a527353bd6376b9f6c4776502 SHA-1: 44dfd0e02ab29083cc7917ae098b3be389e451a0 SHA-256: 51fea3b9a384299b8c4effcc0e855cf493c5a170f56a30c3db7fb38aeed2309c
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to redirect users to potentially harmful content.

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://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/cdf283506b9b99fecd345f4ee838d880/loluvasosegujo.pdf In PDF document text
    • http://darec.sk/files/files/37154126299.pdfIn PDF document text
    • http://zhodnoceni-penez.cz/is/images/FCKeditor/File/43639297262.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/16072ae484057d---jamesarilukunezononigila.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/u4ssmebi6tfa2nbd5khucri2s7/selovazizamuda.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/bd104e347301a89fb0af7e815d815824/vevuvusaxiworikinegi.pdfIn PDF document text
    • http://sattosushi.com/uploads/files/nikijawopapagosafoseleri.pdfIn PDF document text
    • http://trans-serwis.com/userfiles/file/bivedazovit.pdfIn PDF document text
    • https://peilimineko.com/userfiles/file/21451656180.pdfIn PDF document text
    • https://sy-tech.eu/file/getomezojem.pdfIn PDF document text
    • http://burrburroughsfamily.com/clients/55468/File/wunixitivaxonefi.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/146ps6c9dtreh6io72qcdsaver/tozusimufiwojazetitofenax.pdfIn PDF document text
    • http://hoangduy.vn/vn/files/boduwevufunijusisax.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/42650482e2e57c94dc8ff9df85672f26/fawofudolinajurit.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/se7lvhfkaebl8ggs3qlh9cad7k/xuwalapadujaralobexeses.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a71c7828ed2---zalinixitukelekatibadupi.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acc026934fd---nonemefedapemeson.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
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=the+oval+season+2+online+freePDF 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ebba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBBA 4704 bytes
SHA-256: 7b9000c24aa711cf4f11a40ac08d15269c101460f58fece53925df14d9710cf3
font_01_sfnt_off0000fba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA2 11080 bytes
SHA-256: 709e7560990ddf23842d132f8c2c37c0755d086d2315ff70db32879641c1767c
font_02_sfnt_off0001217c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1217C 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361