Malicious PDF — malware analysis report

Static analysis result for SHA-256 41c017ab02beb491…

MALICIOUS

PDF

79.1 KB Created: 2021-06-11 19:05:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 8708e5d613d8f09badfdb378dabfa8bf SHA-1: f5bc6da55dee420774f3d8a8c3668abbd71d482f SHA-256: 41c017ab02beb491880fcd067a8661c580fb9ef4fd5785f7b7e73dcffb0dcfad
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress upload storage and other disposable hosting. These links likely serve as lures for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ketchas.ru/uplcv?utm_term=emotional+intelligence+appraisal+free PDF link annotation
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0da8cad13---samorivawuv.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/ok46kkp2p5dha4p13pr9fej3d1/63179955458.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983c9a6dc8c---80554616817.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/joxumofojidumefizi.pdfIn PDF document text
    • https://auto-rujo.com/images-editor/file/donasazivojoga.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/e18c49742087921d5bab2989dc05cfca/95165484202.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16090397dd6cfd---gimebofuxeg.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/85226870f4ccec6d62c34c52fa975193/nirifovopifisiwiwefojow.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4a5a7d7a8---wibibezi.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/1985300905.pdfIn PDF document text
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/160717dd3c1cd3---96974994324.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160752c3902536---74628158590.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/4f66a576d4c8d0d44540fb5ebdaa2bf9/xutujezavowedemadenivofag.pdfIn PDF document text
    • https://vate-tire.ru/wp-content/plugins/super-forms/uploads/php/files/b06178826bd61e125fc57714f5824ad5/42506686464.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608be8255e49c---1867118698.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/ejk15mpo057ll0g1g5evsad8bp/xepufiwepipivununujeb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e878.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE878 5080 bytes
SHA-256: 8dcaf1782418f9c3b5b4e3515617e27363dbf1fc480d0e5e69471f4f876e6e48
font_01_sfnt_off0000f9a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A0 11160 bytes
SHA-256: c0f2ece27871400dd2dfa6cf90618aaa698ade8f9c657f8f2423fd02f539acdc
font_02_sfnt_off00011f5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F5E 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2