Malicious PDF — malware analysis report

Static analysis result for SHA-256 77e2513aa32bcad2…

MALICIOUS

PDF

74.3 KB Created: 2021-06-14 13:10:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 43bf233d14813d494bf8d6f87faa2a45 SHA-1: b65aaaf494917af011a94cfa51eed662a633a2d3 SHA-256: 77e2513aa32bcad264656a1b34347879b98357d567829b72a7578e64db2f5858
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1190 Exploit Public-Facing Application

This PDF file contains embedded JavaScript and numerous external links, many of which point to compromised WordPress sites. The links are structured as a link farm, suggesting an attempt to manipulate search engine results or redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • 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://coretry.ru/uplcv?utm_term=4th+grade+math+word+problems+multiplication+and+division PDF link annotation
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/243dc8c6cd6a62f34d48902d14bb5d32/zerajuwotisuxame.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16076c8f348f50---pemumulivodazevuwajije.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/0596076a9544ecba833d2558f21fd259/75130478907.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/90a8c25b58ef62885a83d229079b0c3b/6375518851.pdfIn PDF document text
    • http://aucoindeshalles.com/menu/file/69004652641.pdfIn PDF document text
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/c013b75d82ca08c6d2f6f4388517b85c/82353432892.pdfIn PDF document text
    • http://dichvugiayphep.net/hinhanh_fckeditor/file/kowujozidenefugibokodas.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16087a9ee5e548---xinufekakaguref.pdfIn PDF document text
    • http://hiace-yoshikawa.com/js/upload/files/14952414371.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/0950d5e6fa76229ff8bc7f7118278f32/56407129924.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e628f41497---wegimopegixapoved.pdfIn PDF document text
    • http://garageanything.com/js/upload/files/7239502097.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc35e7ed09---tefukawomebuxijuwofi.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094e044abc17---39464676545.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE416 5772 bytes
SHA-256: b1b7ead0520ed2c696b87932097849bff424301bb74c67744ddda894f7954973
font_01_sfnt_off0000f7a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A1 10664 bytes
SHA-256: e97e69a88d3d2f9573242fcbc930d6b5110a95db84b741d54894a308a2983453