Malicious PDF — malware analysis report

Static analysis result for SHA-256 9873c4ed08016153…

MALICIOUS

PDF

94.6 KB Created: 2021-09-10 15:57:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 72c0a26ec84f3a915b0da7c54617f530 SHA-1: fc01e2a5c03d95a1f76cce4f079dd2086721df29 SHA-256: 9873c4ed08016153dd5bed4e7cce0d66c31495bd4164113b439a1741ae4f0da8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates the document is designed as a link farm, likely to distribute malware or conduct phishing. The ML classifier and ClamAV detection strongly suggest malicious intent, with the embedded JavaScript likely facilitating the exploitation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://ha-sine.com/d/files/46648853321.pdf In PDF document text
    • http://aotem.com/data/home/qxu1780220113/htdocs/uploadfile/files/97681812455.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/vosotowufozobun.pdfIn PDF document text
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kusonoxa.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210907_5E4B1EB22AE8B3B4.pdfIn PDF document text
    • https://www.zolmedis.lt/ckfinder/userfiles/files/saxigew.pdfIn PDF document text
    • http://innobiztour.com/FileData/ckfinder/files/20210908_4623A9225F9E0870.pdfIn PDF document text
    • http://kermiradiatoriai.lt/images/files/tuzejog.pdfIn PDF document text
    • http://ekstelekom.com/userfiles/file/janigiditadajon.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161359045bb5fe---xawafomo.pdfIn PDF document text
    • http://eg-connect.com/uploads/editorfiles/file///70561699969.pdfIn PDF document text
    • https://kristaldicarlo.com/userfiles/file/5400223222.pdfIn PDF document text
    • http://sbriz.ru/userfiles/file/pazejokik.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/lakilik.pdfIn PDF document text
    • http://battlegrouponline.com/app/webroot/js/ckfinder/userfiles/files/gixotivuratodunaju.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/domosar.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/36907205944.pdfIn PDF document text
    • https://ayurmitra.com/files/file/19289273970.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/97022156889.pdfIn PDF document text
    • http://ameshamagazine.com/js/upload/files/99160423204.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/mexuvexaboxawagujeseke.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7967c2f4f---53903223663.pdfIn PDF document text
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/derivulesufuguxedezoluse.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=list+of+cookie+clicker+achievementsPDF 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_off00010341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10341 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011b58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B58 10716 bytes
SHA-256: 4002c2296d98eb662f01fa42d0a1cf155f4d13179ea164f02fcf92c7519b6e11
font_02_sfnt_off000133d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133D6 21932 bytes
SHA-256: 6a5bfa240012b0eae28591cfeaaf081c56256823270793576baba608a771d687