Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b53e7924046effb…

MALICIOUS

PDF

81.6 KB Created: 2021-09-20 23:25:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8ff6740466923006d27fc430c9ecc0b5 SHA-1: cf309eefbea3ad5e36fa3a52c0bd8caefc4983b1 SHA-256: 1b53e7924046effb8a8440f8695f6dcf8e2617396fbdb4832cd8dccc91c81cbf
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on disposable domains and appear to form a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely responsible for redirecting the user to one of the malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://altstudio.be/app/webroot/uploads/file/9743884465.pdf In PDF document text
    • http://saltokisport.com/uploads/files/gavudekovukomifim.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16132f05590bdf---60060900131.pdfIn PDF document text
    • http://tantex.org/tantex/tantexuserfiles/file/86357405982.pdfIn PDF document text
    • http://mengnuanua.com/app/webroot/files/files/81331120413.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/74438835230.pdfIn PDF document text
    • http://dorinhawear.com/admin/fckeditor/editor/filemanager/connectors/php/fckeditor/editor/filemanager/connectors/php/userfiles/file/nudasizuxajototu.pdfIn PDF document text
    • https://bold-iot.com/uploads/files/202109111718412677.pdfIn PDF document text
    • http://belst.by/upload/file/fiduwefojazukevibodege.pdfIn PDF document text
    • http://xmzs.org/userfiles/file/48143648848.pdfIn PDF document text
    • https://www.weldcor.ca/public/ckfinder/userfiles/files/79555139018.pdfIn PDF document text
    • http://wefocusdesign.com/upload/files/60101544548.pdfIn PDF document text
    • https://eliteplacementagency.com/uploads/files/35609467853.pdfIn PDF document text
    • https://sibconsulting.com/contents/files/pamaxo.pdfIn PDF document text
    • https://kokomanis.com/contents/files/41862814437.pdfIn PDF document text
    • https://literie-depot.fr/UserFiles/file/wemalarakomozusilanes.pdfIn PDF document text
    • http://denkobarbell.com/_upload/files/76178245421.pdfIn PDF document text
    • https://minervatech.work/js/ckfinder/userfiles/files/fawewexos.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/taratonujekujufirezebize.pdfIn PDF document text
    • http://skalamatbaa.com/userfiles/file/46970769008.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/noxabub.pdfIn PDF document text
    • http://artc-polymers.com/upload/images/files/48916152281.pdfIn PDF document text
    • http://orel-trinity.ru/sites/default/files/file/57231307367.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132bd85a67a6---13922655484.pdfIn PDF document text
    • http://amy-tsai.com/images_express/userfiles/files/kesopinidara.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=video+wallpaper+phone+downloadPDF 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_off0000daf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f308.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF308 10280 bytes
SHA-256: 44aa0f7c5f8642c2fff2ef8ff7d5a0334bc32a06158cf45b1a88d977254a2257
font_02_sfnt_off00010a04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A04 17852 bytes
SHA-256: 30c6cb713433073fe97720d756e395ac9f3462abe8a4ac6dc8bcf2fb01a1f0dd