Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c5fda11b89aa1d8…

MALICIOUS

PDF

77.1 KB Created: 2021-09-16 04:35:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a63763208b8cfa71ac976fff4f724efe SHA-1: af14d4d65eed1eb7785fe36e110cd7f8d814f7dc SHA-256: 0c5fda11b89aa1d89b75acce00564a4d710836d3a442a51c74c4edcee6271cdc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Numerous heuristics indicate the document functions as a link farm, directing users to various external URLs, some hosted on compromised WordPress sites or disposable domains. The embedded URLs and the overall structure suggest an attempt to trick users into visiting malicious sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://huntic.ru/uplcv?utm_term=app+lock+premium+apk+download PDF link annotation
    • http://hide-bo.com/img/tmp/file/46847414764.pdfIn PDF document text
    • https://ivanamihic.com/files/18843102475.pdfIn PDF document text
    • http://rmgoals.com/userfiles/files/zigewotuluza.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/844fdfae687fd24ed5585dcc2dcc9736/56697419584.pdfIn PDF document text
    • http://riviera.az/userfiles/file/tazijusegari.pdfIn PDF document text
    • https://www.burnat-provins.ch/ck/ckfinder/userfiles/files/pujelirodurubutotilosas.pdfIn PDF document text
    • http://www.elstar.ru/uploads/files/66954382817.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138bb764e958---30216031761.pdfIn PDF document text
    • https://yellowstonewildlife.com/zixilowubefe.pdfIn PDF document text
    • http://mobilni-kadernictvi.cz/files/file/biserakibanudefajo.pdfIn PDF document text
    • https://umartravel.com/files/xizodekijifoteguxusij.pdfIn PDF document text
    • https://istanajp2.com/contents/files/46579651638.pdfIn PDF document text
    • http://surveycook.com/upload/tmp/202109/file/lozoxebibabepo.pdfIn PDF document text
    • https://evrenmentese.com/upload/ckfinder/files/lugefu.pdfIn PDF document text
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/29851816521.pdfIn PDF document text
    • http://partnercable.com/files/76594952515.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613137b7007c7---51190276925.pdfIn PDF document text
    • https://phu-komplex.pl/pliki/file/9035298357.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/95950207041.pdfIn PDF document text
    • http://veiligheidssloten.nl/ckfinder/userfiles/files/41194624829.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/81010503149.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/nunikija.pdfIn PDF document text
    • https://hockeymro.ca/docs/file/36418979289.pdfIn 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ca66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA66 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e278.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE278 16876 bytes
SHA-256: 5d5fb45ebee1784bd8b2c85b8af2d9fc3d929e23f5ffa566f0254855831640e2
font_02_sfnt_off00010e49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E49 10668 bytes
SHA-256: f43dfd1d0cf799aa672f4b63ba4fc3ab09b24665762fc5d022b051a0d85fe729