Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd0186c41e2554f8…

MALICIOUS

PDF

81.7 KB Created: 2021-09-16 23:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a7d4e2286c40d25dd07c52c0a1e3164e SHA-1: 18c5dda8c20bbc252a1bf96ac06633d461a94e77 SHA-256: cd0186c41e2554f8c6ed972136decce4857f63fe966a5979072b9dcebc13fd5f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm or redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of embedded URLs and the nature of the heuristics point towards an attempt to trick users into visiting malicious sites under the guise of a game download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613db6a2407d5---42023349945.pdf In PDF document text
    • https://butyfarm.mm520.net/userfiles/files/50538507152.pdfIn PDF document text
    • https://shinko-tw.com/UserFiles/file/6802520669.pdfIn PDF document text
    • https://chsins.tw/uploads/files/202109081057148054.pdfIn PDF document text
    • https://ruxthai.com/ckfinder/userfiles/files/8225156762.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132d2fa7e3d3---22804901796.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/64888755016.pdfIn PDF document text
    • http://nationalcoopadvisors.com/userfiles/files/mekuwijonumasuwuwiwuwakim.pdfIn PDF document text
    • https://betenagro.com/sites/default/files/file/60256155911.pdfIn PDF document text
    • http://sibstroiexp.ru/userfiles/file/42556785663.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/9b969b055c7d8def1260093eecd43552/numunekofulixeriduzedi.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614309d08a88a---96531689980.pdfIn PDF document text
    • http://joeun-it.com/userData/board/file/54058081725.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/3316939310.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135fabc3ae9c---rorekilevawepobulomidi.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210901_053012.pdfIn PDF document text
    • http://ecogestval.com/userfiles/file/wisuzepuvuxotig.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/50850226331.pdfIn PDF document text
    • https://lideregitimpaketleri.com/calisma2/files/uploads/83932134848.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/tejegat.pdfIn PDF document text
    • http://ttfi.org/app/webroot/userfiles/file/63845483171.pdfIn PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/88780608907.pdfIn PDF document text
    • http://xn--j1aai7d.xn--p1ai/userfiles/file/21989175675.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=untitled+goose+game+download+androidPDF 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_off0000d9d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D3 17792 bytes
SHA-256: 173282229dd5d4476a344f10a139830cb95a340b7fd6a31211f40bfa37604797
font_01_sfnt_off0001084a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1084A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012061.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12061 10684 bytes
SHA-256: b6af31f780cbf58e66713951c858ba0f51ccea44d139c6bf41674c406c7a54f2