Malicious PDF — malware analysis report

Static analysis result for SHA-256 9739f6e76a1aa571…

MALICIOUS

PDF

69.5 KB Created: 2021-09-23 13:44:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 095af4bcdee15b34b1171a00cc2b4a43 SHA-1: 8c0e5d804f26a7a5f9943545d111a4ab9780e4d3 SHA-256: 9739f6e76a1aa57170fe2d81da04bbbc16cc08022ddcd79e9226a740f49c9d83
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan variant. It contains a large number of embedded URLs pointing to various domains, suggesting a link farm designed to redirect users to potentially harmful content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or spread malicious links across disposable hosting. No scripts were extracted, but the primary attack vector appears to be the extensive use of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://synerhu.ru/uplcv?utm_term=slope+run+3 PDF link annotation
    • https://orangerun.re/photo/files/lazowomevusepenewoz.pdfIn PDF document text
    • http://dungcucaytrong.com/images/files/82778688027.pdfIn PDF document text
    • https://ikincielinmak.com/upload/ckfinder/files/zazabo.pdfIn PDF document text
    • http://w-w.cn/isee/pfm/cms/uploadfile/fck/file/21048613152.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/baseniwetiwodavaboxogez.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/d5f5f059dbbf4ad3fd68cb8bbe5d2693/40220726336.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/71943580635.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/51e3d155f38f4b0217dcd017aeed6a26/fajomixi.pdfIn PDF document text
    • http://dpengineers.info/admin/userfiles/file/77799245955.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/fuvonamedoteputek.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///nemamir.pdfIn PDF document text
    • http://nickelsgrafikdesign.de/ckfinder/userfiles/files/7797694492.pdfIn PDF document text
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/91440453628.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/40367634231.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-9/file/64557006771.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/zinixojukojukujogej.pdfIn PDF document text
    • http://makinsushi.com/uploads/files/tezofolitatukupi.pdfIn PDF document text
    • http://parentini.it/userfiles/files/dulutinizewikujikozazadot.pdfIn PDF document text
    • http://www.addvanceo.info/userfiles/files/botejisamoku.pdfIn PDF document text
    • https://readandenjoy.ae/userfiles/files/49561700315.pdfIn PDF document text
    • http://piazzademarini3ge.com/userfiles/files/83785935662.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/fidagileve.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/44992148971.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_off0000b1d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1D2 10072 bytes
SHA-256: 3c4089bbc1f36066c9a6ddcff894dddfb64bfed90356586e56875d4258b65ada
font_01_sfnt_off0000c85b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC85B 15760 bytes
SHA-256: 22b98090b48458be087464805df4876fff3b1bf87d86729f7482644e1b5b386f
font_02_sfnt_off0000f0c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1