Malicious PDF — malware analysis report

Static analysis result for SHA-256 423d0332208516df…

MALICIOUS

PDF

81.9 KB Created: 2021-09-11 16:49:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: dd0f479283a892cd28752768b7ff07e8 SHA-1: f5427169c0ac7bda9219c73c5db6a2fa6d3a1fe1 SHA-256: 423d0332208516df1d58a65c38018fe7047379d6500800c0254e4a3d633f5fa2
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to suspicious domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high volume of links on disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lead users to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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://hitourkorea.com/FileData/ckfinder/files/20210906_DE957BED1082D298.pdf In PDF document text
    • http://czyxchem.com/upload/files/futegubujofukeli.pdfIn PDF document text
    • https://minervatech.work/js/ckfinder/userfiles/files/bebiwu.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/6276447601.pdfIn PDF document text
    • https://www.shropshirefurniture.co.uk/admin/ckfinder/userfiles/files/subawigizi.pdfIn PDF document text
    • http://dambi.pl/userfiles/file/50158717783.pdfIn PDF document text
    • http://sentezetutmerkezi.com/upload/ckfinder/files/jeliso.pdfIn PDF document text
    • http://sapthagireesyathra.com/userfiles/file/49291496886.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/pipiwividosezuxesabib.pdfIn PDF document text
    • http://idroter.org/userfiles/files/52929111742.pdfIn PDF document text
    • http://greensquares.in/userfiles/file///lenomafogewigukenavema.pdfIn PDF document text
    • http://yuanyoujie.vip/userfiles/file/7407087014.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/66c61c257e593d94801c12ddc0ec2260/84826169483.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613060505eef3---tuluzopeg.pdfIn PDF document text
    • http://uforoi.com/app/webroot/uploads/files/xepebo.pdfIn PDF document text
    • https://toptenstudy.com/upload/files/BodyFile__6134C1473489A.pdfIn PDF document text
    • http://ipcmanpower.com/admin/style/images/userfiles/file/75623146047.pdfIn PDF document text
    • http://malovanesklomh.cz/images/file/nejamonusowagifinote.pdfIn PDF document text
    • http://k-yoga.org/file_upload/spaw_upload/file/20210909230917.pdfIn PDF document text
    • http://portaldo.eu/contenuti/upload/file/68502193323.pdfIn PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/jagovoxowikakolebagirel.pdfIn PDF document text
    • https://transport-vehicules.fr/userfiles/file/tojarukagi.pdfIn PDF document text
    • http://sicompk.com/survey/userfiles/files/94580970408.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/96943642323.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=breath+of+the+wild+walkthrough+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_off0000ddc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC6 10836 bytes
SHA-256: 95a66f0bb8016a8114b9321bb33f3ec186a481cbdcd9767ed2dba8ad78ed20ef
font_01_sfnt_off0000f6c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ed8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ED8 16708 bytes
SHA-256: 98a3f4278c3a620f6b13ec2f24a92b524afb5d909ddf4a3653c07c6c00a796c6