Malicious PDF — malware analysis report

Static analysis result for SHA-256 53e3a7d1e87c0c45…

MALICIOUS

PDF

87.8 KB Created: 2021-07-20 09:19:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: cd50a41d3a7c8653748c2d0c540f819e SHA-1: f5d7281b2319bb96b30c225d2faca37f367ce606 SHA-256: 53e3a7d1e87c0c456e6d7b20b96e288b3dcd4fb66224c38f6be2044fc5cb4ce0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. It contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, forming a link farm. The embedded JavaScript likely facilitates the redirection to these malicious links, which are designed to distribute further payloads or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16074444644051---55662221799.pdf In PDF document text
    • http://kibbkw.com/uploads/file/68121451848.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/f3ecdjm45fg5uf3o8j2r87o7q0/wixowegaje.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8ecb5856b6---xijaxakamatez.pdfIn PDF document text
    • http://rocb-ap.org/file_media/file_image/file/57561217276.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16080e30f33763---91447615955.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a73b31a9e24---24299780223.pdfIn PDF document text
    • https://syteq-pro.com/userfiles/file/76146933588.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/cr90f72bq6adtkmm1or51skube/90131350137.pdfIn PDF document text
    • http://english-life.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16078a9a3653d5---13055599895.pdfIn PDF document text
    • http://hillcresthigh1971.com/clients/9/9f/9fbf9047a6869172a982db6f42f05a9a/File/38681934342.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0a08353aa---14691295607.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/1ce72d0284e001a9117c69f52c2b88fc/87300570249.pdfIn PDF document text
    • http://schooldistrictservices.com/clients/f/f6/f6ab1571d2cdf5e569af7b76e288b17c/File/tonekoxojenuzine.pdfIn PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/laxure.pdfIn PDF document text
    • https://vestol.bg/files/file/46532711986.pdfIn PDF document text
    • http://ncabhsa.com/clients/875427/File/wogewedabiwu.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/335eb87c42df56c71b33f8c5c2c78b50/86312830375.pdfIn PDF document text
    • http://bjjiffy.com/upload/jemasifenarakubutagerem.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160857af9ae8bf---10180258082.pdfIn PDF document text
    • http://daieimotors.com/js/upload/files/bepefizezerobusatusezowom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=can+iphone+read+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_off0000f590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF590 10312 bytes
SHA-256: 3ed0b24685b9ebdc6c746387c0b0b0995695362d809e2e1b301e7628a8fc7b36
font_01_sfnt_off00010cad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000124bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124BF 16944 bytes
SHA-256: 9d07918c93cfb8e983144c82e0efdecdb8b773b0cfd17791d96db053c000e1bb