Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d441cdc8d642d93…

MALICIOUS

PDF

68.9 KB Created: 2021-10-03 03:22:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 2406254fd295030c67c67534bd525dcc SHA-1: 4c6b0d1fb8b0e8d260ea505633356416438a5b1f SHA-256: 3d441cdc8d642d93f776a31c2634b0d63eff7f7c1898ef6180d162bc0f1d4f8e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The presence of embedded JavaScript and numerous external links, many pointing to compromised or disposable hosting, strongly indicates a malicious intent, likely for phishing or malware distribution. The ClamAV detection and ML classifier further support this assessment. The embedded JavaScript is likely used to facilitate malicious actions, such as downloading further payloads or redirecting the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://zegaoyun.com/calisma2/files/uploads/24710036240.pdf In PDF document text
    • http://tomei4x4.jp/js/upload/files/96171603741.pdfIn PDF document text
    • http://consorzio-csa.it/userfiles/files/65892979836.pdfIn PDF document text
    • https://khonggiansachhanoi.vn/uploads/files/12516275792.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.com/ckfinder/userfiles/files/86409051301.pdfIn PDF document text
    • http://goozzl.com/userfiles/files/sirugekisenigiduje.pdfIn PDF document text
    • https://mediaget.ru/userfiles/files/xazulejaxororumiruvufi.pdfIn PDF document text
    • http://xn--90aoa5aj.xn--p1ai/ckfinder/userfiles/files/nenol.pdfIn PDF document text
    • http://funagamex.vn/PhuongNamGroup/userfiles/files/70110863375.pdfIn PDF document text
    • http://pomelieagency.com/userfiles/files/52861573934.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/8hocus2iihvjj1c7925dqe6jkd/xirizeragu.pdfIn PDF document text
    • http://theorientgarden.iorderfoods.com/uploads/files/toteriwadore.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/4f137d599971145e01a20afc1ffb0bd7/3441126944.pdfIn PDF document text
    • http://djpress.pl/Image/files/95283211118.pdfIn PDF document text
    • https://derfo.info/resimler/files/tikopetuvukevo.pdfIn PDF document text
    • http://adm.stikom-db.ac.id/js/uploads/files/rodajuvizoxokak.pdfIn PDF document text
    • http://e5tbr2.alruaa.com/ckeditor-ckfinder-integration/uploads/files/tulovavaxojopaxozid.pdfIn PDF document text
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/nugagegenimuxa.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149aad33f0a9---96115389191.pdfIn PDF document text
    • http://planao.com/ckfinder/userfiles/files/wiwojizefenemetoza.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/kefemuraxukesinolidi.pdfIn PDF document text
    • https://www.tristar-technology.com/ckfinder/userfiles/files/xekozoxe.pdfIn PDF document text
    • http://genbreedpublisher.com/files/upfiles/file/13464744819.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=collinear+in+mathsPDF 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_off0000afac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFAC 10404 bytes
SHA-256: 819d60a9c4b5f866f1eb5dad1fdc3d30befe42ce57ef0e1fc81cc0e8c153582e
font_01_sfnt_off0000c70d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC70D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000df1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF1F 15580 bytes
SHA-256: 88c8eb2ce45b5a04869aecef9410a40280fe0ffc2a535f5606f5e28ee8d85563