Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b04f043abf54b46…

MALICIOUS

PDF

80.5 KB Created: 2021-09-09 00:32:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c2f55db12824e261034e907ac9d0509b SHA-1: 8f408b7a1a2cfb5d617a730804b458d03cde1b9c SHA-256: 3b04f043abf54b46802c38a3cd74226b892e218dafc2cfba1b16208de5398975
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also contains numerous external URIs, including one identified as a link farm on disposable hosting, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the execution of JavaScript to redirect the user to a compromised site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://bckbytow.naszbip.pl/img/upload/files/kopalasukadolusenagez.pdf In PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-1/20210901100423361429.pdfIn PDF document text
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/xumelujojanipufemagavef.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16134afa5c1bd8---17229562395.pdfIn PDF document text
    • http://mosjob.ru/images/file/2601865902.pdfIn PDF document text
    • https://die-elke.de/cms/elke_page_files/file/33372777528.pdfIn PDF document text
    • http://hzxf.com/images/upload/File/95718859797.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/42570747606.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/9721163c4cc577e1831590ade912457a/103044681.pdfIn PDF document text
    • https://creteotels.gr/FCKeditor/userimages/file/94695871529.pdfIn PDF document text
    • http://lionsmarsala.it/userfiles/files/pukolom.pdfIn PDF document text
    • http://sreema.org/FCKeditor/file/digelobivowem.pdfIn PDF document text
    • http://glassick.com/userfiles/file/zetelibufomidudabenuj.pdfIn PDF document text
    • http://rialta.ie/userfiles/files/rejumaxedanotatifixode.pdfIn PDF document text
    • http://www.groupementpecheduloir.com/ckfinder/userfiles/files/26422985394.pdfIn PDF document text
    • http://tbff-bygg.se/img/files/4920278232.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/90816927640.pdfIn PDF document text
    • https://tanhaithanhvalves.com/quangcao/admin/file/lesisimoxikekoxe.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/64318967978.pdfIn PDF document text
    • https://digireg.sk/upload/kizoterukomojaxerinoburod.pdfIn PDF document text
    • http://terralis.eu/catalogue_dynamique/file/64063283473.pdfIn PDF document text
    • https://www.tulsarad.com/my_content/js/ckfinder/userfiles/files/83430292209.pdfIn PDF document text
    • http://gzwep.com/img/file/202198141320.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/41583245911.pdfIn PDF document text
    • http://toszegisuli.hu/userfiles/file/zivavolanirinunebu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+write+debate+in+english+class+11PDF 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_off0000d6f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F5 17076 bytes
SHA-256: b72b6eb63519bb83c08514500992d7040d13d5aace551049050ed538be691e46
font_01_sfnt_off000102eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B02 10916 bytes
SHA-256: 5fc679edf89d89d5815df915adae8e45ea9985e553121113c4f0aa18f17fccff