Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb84d9c732d75cb2…

MALICIOUS

PDF

81.0 KB Created: 2021-09-10 12:25:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: cd5fe4ba9aac902d9e32d19d1c2ae43c SHA-1: 26be80e9c5050d6f39bec8f465b34420e46b219f SHA-256: cb84d9c732d75cb2fea0ff54fa1304dca16c849a60d713e57d85337132c1b146
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, suggesting it functions as a link farm designed to redirect users to potentially harmful content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a large number of links on disposable hosting, further supporting a phishing or malware distribution motive.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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://coretry.ru/uplcv?utm_term=smartphone+usb+tethering PDF link annotation
    • http://elma1.ru/!upload/files/lafazigudil.pdfIn PDF document text
    • http://fazendasaojudastadeu.net/fotosempresa/files/kuverisodaze.pdfIn PDF document text
    • https://hung168.tw/UserFiles/files/19735708980.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/56012439998.pdfIn PDF document text
    • https://asztromiskolc.hu/ckfinder/userfiles/files/19726992792.pdfIn PDF document text
    • http://erisalaw-chicago.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/1161224549.pdfIn PDF document text
    • http://studioarchoggianiepartners.it/userfiles/files/86856498404.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16137b711e466e---lewum.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306932954f9---jelefosejotakesizivof.pdfIn PDF document text
    • http://flyingkirin.com/uploadfiles/file/08192257528.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/63110331164.pdfIn PDF document text
    • http://termocity.by/pics/files/sajubum.pdfIn PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/52379577515.pdfIn PDF document text
    • http://surmounttravel.com/userfiles/files/99815951384.pdfIn PDF document text
    • http://www.pics4us.de/userfiles/file/4846161688.pdfIn PDF document text
    • https://argekaucuk.com/nbg/upload/files/78808936404.pdfIn PDF document text
    • http://biomehl.com/images/content/files/49260712082.pdfIn PDF document text
    • http://cristal-in.fr/userfiles/file/dexekuv.pdfIn PDF document text
    • http://atrsara.ir/resource/files/3263550523.pdfIn PDF document text
    • https://godahoian.com/app/webroot/upload/files/nizejefidoruwejogagev.pdfIn PDF document text
    • http://www.prctech-th.com/ckfinder/userfiles/files/88193514646.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/dogur.pdfIn PDF document text
    • http://studioboscono.it/userfiles/files/47578480335.pdfIn PDF document text
    • http://ugrctrani.it/userfiles/files/voravuban.pdfIn PDF document text
    • http://ksiclubcom.ksiclub.org/svnprojects/DHD/Source/images/files/24298625989.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_off0000d7a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A5 17400 bytes
SHA-256: 1a1effe0b8de1978a23b3361226ac711392eb78f41718ac5f1337955517dbbac
font_01_sfnt_off000104ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104EF 10968 bytes
SHA-256: 1f12666915707001fa26829d09d2ba01878e72fb99be9ef778c1e11523716aa9
font_02_sfnt_off00011df8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1