Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8358f8ad611a110…

MALICIOUS

PDF

79.8 KB Created: 2021-09-17 16:26:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3a540a88f6f8a5c87ec70392c4334133 SHA-1: 900e8d6bda8375f7ec8e7e865200e19cb0adf73c SHA-256: c8358f8ad611a110cf5395d1be710ffcc84435ece378699d68206864b7bb49c2
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains embedded JavaScript and numerous external URIs, suggesting it's designed to redirect users to potentially harmful websites. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating a large number of links hosted on disposable domains, a common tactic for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crysiq.ru/uplcv?utm_term=ios+hungry+shark+hack PDF link annotation
    • http://bonaparte-kerkrade.nl/fckeditor/ckfinder/userfiles/file/difebetimawekapogifufub.pdfIn PDF document text
    • http://plusdesignwebsite.com/userfiles/file/tubapuf.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/15464981104.pdfIn PDF document text
    • http://aotwresort.info/ckfinder/userfiles/files/birivu.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/toxigejoguz.pdfIn PDF document text
    • http://chrisnoblelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zetodejuvuvobop.pdfIn PDF document text
    • http://limoride.net/gallery/file/mawezanadevuvesot.pdfIn PDF document text
    • http://dreptultau.hotnews.md/upload/userfiles/files/83162277945.pdfIn PDF document text
    • http://aci-immobilier-douai.fr/userfiles/files/pifufolomataxa.pdfIn PDF document text
    • https://mar3ol.com/Files/files/sobewazupuzitesodazoxuzew.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/zuzubilatigerivo.pdfIn PDF document text
    • http://ozdoby-betonowe21.pl/Upload/file/18923573470.pdfIn PDF document text
    • http://crimesla.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/28084750423.pdfIn PDF document text
    • http://daieimotors.com/js/upload/files/48616862872.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/41291878383.pdfIn PDF document text
    • http://abwingssuffolk1.com/uploads/files/87181755240.pdfIn PDF document text
    • http://tecnoservizi.com/userfiles/files/zifakokelidejizodumi.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/a0375adb7e0642bc2864e2de49483db7/nofufuruboselewa.pdfIn PDF document text
    • http://goldendazzle.com/upload/quangtri/files/35544145957.pdfIn PDF document text
    • http://pelejas.com/IMAGENS/CKFINDER/files/donurebukexenuvonog.pdfIn PDF document text
    • https://ciar.vn/uploads/image/files/14325441290.pdfIn PDF document text
    • http://xmzhj.com/UserFiles/file/22289670580.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/26081158073.pdfIn PDF document text
    • https://tch.lu/files/files/57570525335.pdfIn PDF document text
    • 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_off0000d33d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD33D 10400 bytes
SHA-256: afa0f93dca14e84cd42abdf09a32e209c5abfd3b66d01755d40ef3cbec6b4d84
font_01_sfnt_off0000eac0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000102d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D2 18224 bytes
SHA-256: d7dc9d8779e5ccbda0bc0a82d69571b94ee32da247b56600717a4c3b96af2904