Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d55ee4a042fd502…

MALICIOUS

PDF

83.8 KB Created: 2021-09-15 13:12:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d66a03a8d553306dc2c5ec998fdab39f SHA-1: cc49400455d754cb5a14b341b4354ae96b659595 SHA-256: 6d55ee4a042fd502e11fd5534f2cb7659fe1365a9a1f5efb06b63a253c20cf18
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous links to external PDFs hosted on disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to exploit vulnerabilities or trick users into downloading further payloads. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics confirms the use of algorithmically generated URLs on potentially untrusted hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://jeansresource.com/js/ckfinder/userfiles/files/fakibosuzagu.pdf In PDF document text
    • http://metallpress.info/files/46531011617.pdfIn PDF document text
    • https://ssmahavidyalaya.org/lion/uploadedfiles/fck/files/file/vemevibafowutikirilokawi.pdfIn PDF document text
    • https://congnghiepxd204.vn/upload/files/1844048302.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/bewijimupe.pdfIn PDF document text
    • http://jcbcharpentebois.com/ressource/site-image/files/kipunovaxe.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/64963679795.pdfIn PDF document text
    • http://thaide.org/userfiles/file/89595442556.pdfIn PDF document text
    • https://jyapa.com/jhuoyue/uploadfiles/39656951573.pdfIn PDF document text
    • https://dailyhondaotomientay.com/upload/files/takoxurusenej.pdfIn PDF document text
    • http://ryyw.com/upload/files/2021/09/202109070945156694.pdfIn PDF document text
    • https://anandalaya.in/resources/file/bulogebaxemelifomixu.pdfIn PDF document text
    • https://planet-pvc.com/upload/files/fudegedabolunaguxamowofu.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/161368e458fb43---45989119754.pdfIn PDF document text
    • https://bazk.info/public_htmluploads/file/36275896189.pdfIn PDF document text
    • https://ontech.vn/images/ckeditor/files/35751494653.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/0d9c20b9af8da6ea1fd849d7d94af7ee/fegatikisubewowanuf.pdfIn PDF document text
    • http://fuerst-architects.com/uploads/file/pokefowetuxekizopi.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/90806411112.pdfIn PDF document text
    • https://www.luxboss.com/ckfinder/userfiles/files/30834576064.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/18606630658.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=give+me+liberty+seagull+5th+edition+ebookPDF 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_off0000dc47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC47 19420 bytes
SHA-256: 309a1bf21f46489de71b98c5cd4573883165d418dac7b4c43b13500fb84ee27e
font_01_sfnt_off00010f01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F01 11380 bytes
SHA-256: 7be9a1defb3afb333abaa2b7c2e5050780f7240469532943de8a01d777a78bca
font_02_sfnt_off0001298c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1298C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1