Malicious PDF — malware analysis report

Static analysis result for SHA-256 66f8e967966732fd…

MALICIOUS

PDF

77.6 KB Created: 2021-09-03 05:44:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6692e1ecacd552165a3ab410c5a2509d SHA-1: fbd00469265e38f19505101d4ebba14c01250749 SHA-256: 66f8e967966732fd3dedfa3177a12b08450950fad0cc3752794af0cdf57d142e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to compromised CMS uploads and disposable hosting sites. The embedded URLs suggest a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://banquat.com/userfiles/files/refebariziletuferevupon.pdf In PDF document text
    • http://zge-led.com/luodan/images/userfiles/file/11851579805.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/safawenuro.pdfIn PDF document text
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/78488385533.pdfIn PDF document text
    • https://gwynharmon.com/home/gwyn/public_html/ckfinder/userfiles/files/lonowikibuju.pdfIn PDF document text
    • http://dalhousieretreat.com/cote_dor_import/admin/ckfinder/userfiles/files/gujif.pdfIn PDF document text
    • http://aescantabria.es/upload/fckeditor/file///86586329064.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50286330893.pdfIn PDF document text
    • http://biomax.shop/filespath/files/20210820070844.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f69d5c9287---sajupijelejol.pdfIn PDF document text
    • http://lenosada.sk/editor_uploads/files/xopiganit.pdfIn PDF document text
    • http://prunay-en-yvelines.fr/ckfinder/userfiles/files/bowerujutesedux.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210617/1359094174.pdfIn PDF document text
    • http://ducthoaudio.com/upload/files/kivoripepexeviba.pdfIn PDF document text
    • http://cameradungphat.com/uploads/files/54029499766.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/vidugakolevowijujusixara.pdfIn PDF document text
    • http://babamoleskine.com/files/file/17385054232.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f9e482f06---sexototapetebo.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/06e4e9eb3a699bcc4043e79a07181331/gixis.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/16331999811.pdfIn PDF document text
    • http://rubivina.com/Images_upload/files/77035969254.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/9969855952.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/wugejot.pdfIn PDF document text
    • http://officinedesign.it/userfiles/files/notojinepafu.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/55802016269.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=bartkowski+chirurgia+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://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_off0000c8bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8BB 18424 bytes
SHA-256: 6afc7d0e27c3227703495c63bc7173a984ba35bb3fafe3f17512b0b05e5f337c
font_01_sfnt_off0000f79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB3 10948 bytes
SHA-256: 309da63d2ca81c2ac50c961f73fb7366c85afd15056e98942edb7d2dca60b8e0