Malicious PDF — malware analysis report

Static analysis result for SHA-256 2dc27a463f736c88…

MALICIOUS

PDF

81.7 KB Created: 2021-06-20 22:31:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 8d3b3b88bed87b621e9b1f154adaca7c SHA-1: 3df950bb47ab2aa8219e8d2c7dfecb98e602da29 SHA-256: 2dc27a463f736c8873ed0cf8d5d5489ce00e255a21b0a893e5ce9e342c524140
156 Risk Score

Malware Insights

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

The PDF file contains a large number of links pointing to various domains, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these link farms. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, suggesting it was programmatically generated.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://vieclamxaydung24h.com/upload/files/bemilubagu.pdf In PDF document text
    • http://amadpich.com/userfiles/file/xorezamisilawovimoze.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce776d441a---2543341478.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160853bea5cf42---woputesepiwobexabutawiwil.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16087e1a99575d---tukuvasapoluzila.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file/%5C/2021060714255368.pdfIn PDF document text
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3bf9c01ed---dutakedikijidurez.pdfIn PDF document text
    • https://davaocarrental.com/images/file/nudulope.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a85f93d61c0---10538885722.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/aff89546618df3bbbdc08d2aa67a2f9d/54533086215.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f9adfafc407fb9ccb55fa448ce49e267/nigujamajalepalogetalojo.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/jefevopejufilu.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/88678795041.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16077ac48347d3---1959713661.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/xiwijesugexonar.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/111e12f03b18f82cea1876c0a8835235/wisalumej.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160721a627a247---jozusovutakekomabifidomoj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=minotaur+race+pathfinderPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001033c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1033C 5036 bytes
SHA-256: d806066193c35f9a521b06a120e961ab8dcbeaa383010a592bc63b5094605a71
font_01_sfnt_off00011468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11468 11008 bytes
SHA-256: f8bdd2eaaa432dc6154c7dff3682967bc6f5beb092b60eb8f1b8454ce2020792