Malicious PDF — malware analysis report

Static analysis result for SHA-256 0ef88673dc8958a4…

MALICIOUS

PDF

86.1 KB Created: 2021-09-20 17:06:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 46f9e238ea4a55e2889173b74ed39a97 SHA-1: ee809a48167e077e96aa6d5a00ab09fbfc60f2f7 SHA-256: 0ef88673dc8958a47a9c0ba67d7ca950a18d6348f7a26b4605232c32d78f38e6
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress sites. The ML classifier also strongly suggests maliciousness. While no scripts were directly extracted, the PDF structure and link farm nature suggest an attempt to lure users to malicious destinations, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b97e766a99---57155837124.pdf In PDF document text
    • https://icrs-as.com/userfiles/file/belusagufizikifav.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/002c1bf706b590f3f7538892fcfa9687/42248762677.pdfIn PDF document text
    • https://stonebuild.bg/f/uploads/files/86182171114.pdfIn PDF document text
    • http://hanasushichoice.com/uploads/files/vevakevuni.pdfIn PDF document text
    • https://istruttorecinofilo.it/userfiles/file/xaxasokida.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/161412fad7d0f5---venosizarezat.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/32061341376.pdfIn PDF document text
    • https://buffinvestment.com/upload/ckfinder/files/55157044737.pdfIn PDF document text
    • https://adeptos.clevercloud.pt/images/items/files/84267133464.pdfIn PDF document text
    • https://nayyaralidada.net/alpha/ckfinder/userfiles/files/xugerarotonoletedusapaz.pdfIn PDF document text
    • http://gmart-express.com/demo/uploadpic/file/rabutatoreze.pdfIn PDF document text
    • https://resonanceacteurs.nl/userfiles/file/52688174801.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/piximogizumiruxemenab.pdfIn PDF document text
    • http://delve-cr.com/uploads/70019589082.pdfIn PDF document text
    • http://whuntex.info/userfiles/file/xitari.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/tijiwu.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/17111932417.pdfIn PDF document text
    • http://foxadv.net/file/24824404883.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/e9e1ccd0e32026a0ad05635609bb11d4/vuliberedumutaletubij.pdfIn PDF document text
    • http://lovelyspa.net/ckfinder/userfiles/files/72185064206.pdfIn PDF document text
    • https://aucordechasse.fr/vosImages/57143376974.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=best+android+cloud+gamingPDF 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_off0000eee6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000106f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F8 16612 bytes
SHA-256: 11626801f9723003a721a985b2fd0950e875f6fb944bf8f1101f5099b52bd2e5
font_02_sfnt_off000131b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131B9 10864 bytes
SHA-256: 9cebf46116b9c2c403b4dd66aed3c546376a377eaba1ec056c35cb5ddfd6d4db