Malicious PDF — malware analysis report

Static analysis result for SHA-256 eb0b21f255fd486a…

MALICIOUS

PDF

70.7 KB Created: 2021-10-04 01:46:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3d376dfcec9f226f5547ebd4222c74b7 SHA-1: 65f320382dcfabf116bdc916d48cb9a5e241c921 SHA-256: eb0b21f255fd486aae48d97105805efa66f0a51ac6166e0622ed06e37a4ceec4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects the user to external URLs, as evidenced by the PDF_URI and EMBEDDED_URL heuristics, with one such URL being http://roocenter.ru/upload/file/kudemozetuliso.pdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://roocenter.ru/upload/file/kudemozetuliso.pdf In PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e08df84c14---64002116014.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/jeroderosukupewof.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/joduzirerivi.pdfIn PDF document text
    • https://betentour.com/sites/default/files/file/nelegu.pdfIn PDF document text
    • http://nanjing.chinatupai.com/web/js/ckfinder/userfiles/files/55499389134.pdfIn PDF document text
    • http://savaksangida.com/resimler/files/90615870471.pdfIn PDF document text
    • https://monyetmesum.com/contents/files/78457350701.pdfIn PDF document text
    • https://xn--90aoja6ahg5ds.xn--p1ai/uploads/files/5128861013.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1615a2b85bb175---vulivolavakozurepejumoz.pdfIn PDF document text
    • https://eagle-aviation.com/userfiles/files/27588696653.pdfIn PDF document text
    • http://whdhgs.com/uploads/file/20210923235611705.pdfIn PDF document text
    • http://sweepinstyle.com/userfiles/file/26350310817.pdfIn PDF document text
    • https://yodishit.com/uploads/userfiles/file/68489667671.pdfIn PDF document text
    • https://sibiucuratenie.ro/fckeditor/userfiles/file/20126603566.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/zosavi.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/magaxavevosenenuxewemod.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/63767393289.pdfIn PDF document text
    • https://chennothinterios.com/uploads/file/20943258755.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/jitowadonimabelekafas.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/visegaxiwajuxija.pdfIn PDF document text
    • http://ghefootmassage.com/fckeditor_userfiles/file/zujemogejitapegusun.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/bebowubematoposudixevibu.pdfIn PDF document text
    • http://a-pluset.com/userfiles/46463046928.pdfIn PDF document text
    • http://108shiva.com/userfiles/file/In PDF document text
    • http://kitpaisal.com/mypicture/file/93111141008.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=interferon+based+therapyPDF 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_off0000b39b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB39B 10664 bytes
SHA-256: eb2a2521b0c6865b15849a334063a49191a9e29a99dce1a3c94f40729b2017be
font_01_sfnt_off0000cbc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC6 16108 bytes
SHA-256: 303e052d897a17624ff2982b82f0055a5ecd67bd9ffa1711f8fb5ab5c08f1aa4
font_02_sfnt_off0000f539.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF539 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1