Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb53910539ef129e…

MALICIOUS

PDF

86.4 KB Created: 2021-09-15 03:58:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 676a78dcd65e88e50a403e1a2c3fec31 SHA-1: 6245e92229dfcc860b8975f972a15a45edd5e8df SHA-256: cb53910539ef129e9c6cecf7ebb204bcc7a8466d3c1cd5e14db3bdda7b145cb4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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://irlanc.ru/uplcv?utm_term=tekken+6+android+apk PDF link annotation
    • http://rulife.ru/ckfinder/userfiles/files/81740919022.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/rileziwipumus.pdfIn PDF document text
    • https://viktorina.ledoritulys.lt/files/22222831544.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/630aa40b58a7eb855c8a3fcaba75b35a/gaxowasowedano.pdfIn PDF document text
    • https://kubermatkaplay.com/ckfinder/userfiles/files/nejidaforobiluvuxaw.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/lijajadisavineru.pdfIn PDF document text
    • http://roycraft.ca/userfiles/file/tadobenufopukozo.pdfIn PDF document text
    • https://xn--hjrnskadeakademien-mtb.se/userfiles/file/6874332863.pdfIn PDF document text
    • https://campfun.myhost888.com/upload/ckeditor/files/815984116.pdfIn PDF document text
    • http://hglobaltour.com/FileData/ckfinder/files/20210909_18B42F271EBC6896.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/bemexajerazajemit.pdfIn PDF document text
    • http://sintjorisparochie.nl/userfiles/file/lugevisuruwerab.pdfIn PDF document text
    • https://hattoco.vn/images/ckeditor/files/87392384727.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/161383cb2e436a---45061474988.pdfIn PDF document text
    • http://eatoceanic.iorderfoods.com/uploads/files/59114403248.pdfIn PDF document text
    • http://centromp.it/userfiles/files/fevaw.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/16134366b65cbc---vekolopidanasotovumakisab.pdfIn PDF document text
    • http://thibangoto.com/app/webroot/uploads/files/88342361754.pdfIn PDF document text
    • http://citty.org/images/uploads/file/jalekatowopafotorewi.pdfIn PDF document text
    • https://home-consult.lu/userfiles/files/tobibolikobawo.pdfIn PDF document text
    • http://giaexploring.it/userfiles/files/13449170868.pdfIn PDF document text
    • https://quangtriasianwindow.com/uploads/image/files/jebojodivamenatanategiw.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/dofekanufokurujaragabivos.pdfIn PDF document text
    • http://ncdesign.it/userfiles/files/59868434948.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_off0000ec52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC52 18588 bytes
SHA-256: e4a93ff9e6fcab7bc83367d00e80a52e4ae0ca35e86764da8b0f3f9ae8ee5b08
font_01_sfnt_off00011cac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000134c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134C3 10296 bytes
SHA-256: d700cd526f935c2c8959c37669d45c42ec35d1b8e078f16b58acdb9a8d9bab38