Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc4335165cd670d4…

MALICIOUS

PDF

79.5 KB Created: 2021-09-14 01:45:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 23ba36aad4bce7fc5d96ac4bd11bdd2c SHA-1: 7a9e2500337246647eddacc6de0ed0b1ebf91509 SHA-256: cc4335165cd670d4c7568dc521f2b63bcd98aa6aea8654dd76804a652b40ae2c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript, a common technique for exploiting PDF vulnerabilities or redirecting users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is designed to host many links on disposable domains, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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 http://krukaiart.com/userfiles/files/kekodese.pdf In PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/jotifurorabikawosuxut.pdfIn PDF document text
    • http://vetranhtuong.info/luutru/files/35251840429.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-12/20210912151628216408.pdfIn PDF document text
    • http://studioarchterreni.it/userfiles/files/35992675767.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/nomoxizubotetoguxuzap.pdfIn PDF document text
    • https://eirai.org/editor/ckfinder/userfiles/files/tezageg.pdfIn PDF document text
    • https://henseltech.cz/userfiles/file/25942444819.pdfIn PDF document text
    • http://eurogeographyjournal.eu/admin/fckfiles/file/tejodivezunowe.pdfIn PDF document text
    • http://vititanon.com/user_img/files/81381361929.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/xamudebozur.pdfIn PDF document text
    • http://speckrepeg.by/UserFiles/files/87940355307.pdfIn PDF document text
    • http://www.grupoaccs.net/ckfinder/userfiles/files/87351270691.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/devibapub.pdfIn PDF document text
    • https://photojet.bg/userfiles/file/vevivudeperowosokil.pdfIn PDF document text
    • https://www.eos.org.eg/ckfinder/userfiles/files/27250589555.pdfIn PDF document text
    • http://inoxbienhoa.com/upload/files/nitufusor.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcc5d997c2---xotadolalibojonalaxulu.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/7b4b11df4d9b79ee08c8518b9e26786e/91579056047.pdfIn PDF document text
    • http://www.ville-civaux.fr/admin/js/ckfinder/userfiles/files/20949929913.pdfIn PDF document text
    • https://sukhayurveda.in/userfiles/file/mitibufoputidelo.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/mixulaj.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/88476398824.pdfIn PDF document text
    • http://jongauger.com/userfiles/file/89376545501.pdfIn PDF document text
    • http://uitetenindex.nl/images/uploads/25481070744.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=area+of+rectangles+and+triangles+worksheet+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_off0000d31e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD31E 16784 bytes
SHA-256: 91e83e4f1371bc596270eaf85b291358cadc277c42bdbb2383deaada38701ace
font_01_sfnt_off0000fe13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE13 11060 bytes
SHA-256: ed539f59d635bfffe87beacd15cde4f1eeb48bbecd23be606a29818a00cdfa7c
font_02_sfnt_off000117a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1