Malicious PDF — malware analysis report

Static analysis result for SHA-256 4054c8139d7a40d5…

MALICIOUS

PDF

101.1 KB Created: 2021-09-02 22:23:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e5f80286c2a313feb7cb552508edfb76 SHA-1: a3d8332d08b2d8c71d3e7eeb0655f6e373cecd1e SHA-256: 4054c8139d7a40d57e83a198897a2b22375bed733cdc694044795de465baa205
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript to redirect users, suggesting an attempt to deliver a second-stage payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 http://hiddenroots.org/clients/19739/File/fugunigoxupetesipa.pdf In PDF document text
    • http://www.contectrade.hu/fckfiles/file/88712385716.pdfIn PDF document text
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/c5b0432mbef36n6kiuaasdfs1j/99416408963.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-5/file/5897631215.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/6245014312.pdfIn PDF document text
    • http://ixtvs.de/_upload_bilder/_filemanager/file/70992225845.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/katuwusajugerugix.pdfIn PDF document text
    • http://tehnicgaz.eu/files/file/78528665480.pdfIn PDF document text
    • http://toptoptraining.ru/img/upload/file/dewaxapikuwewax.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/zijosiguxabunagerutiguxo.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/zibeko.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/tukupinewotokiw.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/93e47j3utfpaomlgltm4tp2h5q/16589703929.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/xitivexixes.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/xiwepoj.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/398334b93783fe99844829a9c3e93938/fumevuruwemom.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/4a38phkiomnpmea1brat6dl97u/24789602413.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd6f9910b4---boruj.pdfIn PDF document text
    • https://coffeetuanvang.com/Images_upload/files/folole.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a529b5883e---43309342021.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c687d774bbb---26718514873.pdfIn PDF document text
    • http://traviet36.com/upload/files/85713355091.pdfIn PDF document text
    • https://flardochform.se/userfiles/file/10857315814.pdfIn PDF document text
    • https://service-panev.com/userfiles/97843407688.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607f45538e161---1358093189.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=exercices+corrig%C3%A9s+sur+l%27atomistique+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_off00011cd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CD8 11380 bytes
SHA-256: 5afc227056a9b1e8c8ce19927e2f75bbea5d29de7a01deb210bfb0305a5af5b7
font_01_sfnt_off000136f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136F4 21116 bytes
SHA-256: d6672015a1fb3101a1e0c06ac79fd47f3e4c04c784f03a60ac0e47ec2ef4719f
font_02_sfnt_off00016bb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16BB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1