Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3e4c2b63d996d29…

MALICIOUS

PDF

76.3 KB Created: 2021-06-23 03:04:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 68418fdf882d2810d20f22defdef7001 SHA-1: df346959aca59bec826600033d01f44e709c2de1 SHA-256: a3e4c2b63d996d29f0a00541f101ab2a118c8cba648a3bb3361a4b39db48f4a6
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a fake browser/software-install lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://nomylo.ru/uplcv?utm_term=download+tor+32+bit PDF link annotation
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/de9a62462696058fa7a37bf8517df81c/wuragokolefudimumat.pdfIn PDF document text
    • http://alexanderjamesbackcatalogue.com/userfiles/file/gikokoxodamarororugu.pdfIn PDF document text
    • http://anpo.vn/upload/files/88418574887.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a150e8376e4.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/d80b4fdbe86fee89496e5d21c27ff923/baramijorefexugugiloteji.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160723ee913b80---40471429097.pdfIn PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/6543e4adee67e6a1ca86794ef6e17bd9/44067561480.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608073e302c1e---22530206262.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/o2fkb78vjsugengfpnli8vh728/95567864608.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/wupajapimubisul.pdfIn PDF document text
    • https://annjulieskarpmo.com/userfiles/file/sigerub.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/63945875483ae664e31c905c94f98ce9/47954389214.pdfIn PDF document text
    • http://cityhighclassof77.com/clients/9/9e/9ea685038b5a197d2022a69b8c6b162a/File/vorux.pdfIn PDF document text
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/6167f352aae9c94608e7b3ba04e67ca9/rurirufivakutijuzaxoliva.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a905d14e299---jumupevamo.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1FB 5168 bytes
SHA-256: 273fa32faefb75a8772ae62cf3c266ce081733dbc2a9123fdaa8f5b2d7e4c98d
font_01_sfnt_off0000f3aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AA 2424 bytes
SHA-256: 85ea828da8c6d61c1ccc22fa163dcd90e276231d21153a7abe371e38017249b6
font_02_sfnt_off0000fe44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE44 11192 bytes
SHA-256: 8f1b6d0ce1bd70ca9ed4d036a9b195a87e1520d8afd4fb029305e244080767f5