Malicious PDF — malware analysis report

Static analysis result for SHA-256 3db3209cdbe82ae7…

MALICIOUS

PDF

62.0 KB Created: 2021-06-23 14:48:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 52413d1ef65c44ad88ad6c2fc902fafe SHA-1: 4bf13d07468c33ddd3c5e4b65e6acc7914ba1751 SHA-256: 3db3209cdbe82ae7a30fec488b50767e6b429a53c81131b0b12310f17217e2eb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by multiple heuristics, including a machine learning classifier and ClamAV, as malicious and likely phishing-related. It contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish for credentials. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://atamergranit.com/userfiles/file/sititamadimu.pdf In PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071bf21bba74---fowaruzejekevuparoxaso.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/9u8d6b4mn5mv1g8t8d451sbiu0/41973150004.pdfIn PDF document text
    • http://tribo.kz/userfiles/File/zoboganukatujolerosevowuj.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/077638ee7197c2de59dff9589f56416d/koduwobotojobosumumodet.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/0e6ba7db166761af6a3aa535beff7657/66243200683.pdfIn PDF document text
    • https://organicfertilizerproduction.com/d/files/81080686410.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b3ecf4f97d---15855888871.pdfIn PDF document text
    • https://fontaine-eva.fr/userfiles/files/33270417736.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8b27603ad---fofogu.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086b2d0633a3---63369887280.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160b9194fa4354---mukizunajedobuferugawa.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c486e37e9a5---98851180279.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/f6559ef0f2a9153d862a5612f5ec8224/21508845611.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9c50ea023---24296805085.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160d2182094574---12136369673.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=yahoo+usa+answersPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b7ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7CA 4792 bytes
SHA-256: 5da7a3df8bf97c9eb7737102d4b91f12bf732330277a573bac78e40d6e8af611
font_01_sfnt_off0000c823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC823 10364 bytes
SHA-256: 3444817cc8e54f08c74fec755a9f3d3b23925599361a41afd8b1576ca5b77779