Malicious PDF — malware analysis report

Static analysis result for SHA-256 943625d4c2717a27…

MALICIOUS

PDF

75.9 KB Created: 2021-06-09 14:19:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: ba42170485dbbab0e3fb9bdd7e3c0891 SHA-1: 075f24472d12a97b9386471a92fd6ac444a44cc3 SHA-256: 943625d4c2717a270e1e44b0bd234c357a91272a07d9b2d43b55d453c3c24a09
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, suggesting a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity, likely involving the exploitation of PDF viewers or redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crysiq.ru/uplcv?utm_term=koplayer+emulator+requirements PDF link annotation
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160834e5f6473b---55297599520.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/niximaxitobi.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087c5d9d9d84---17958414312.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/mulofokopovamufagidaxu.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc23489404---29089644049.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16071a7d1d0682---vivasat.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/wofuki.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16088b60f4546e---pemoxowoxebiwo.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072822e45421---kololunesimiro.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/e3eb16ad03dae29014bd2732198df1d0/76342931168.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/r6ahb0ehi2re9bnogphk6oj390/32008322904.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c05357252cb---titezi.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/all66iho5jg7qnp21ptsgsl9f7/56983055622.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087272a27490---bomamixisebabe.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609152d9af603---9683020916.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_off0000e86b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE86B 5164 bytes
SHA-256: dfacc8914c1796f5f8767794a29ba19157a12265ccfa7711d70d3863a503439a
font_01_sfnt_off0000f9f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F0 13072 bytes
SHA-256: 8af20da5d3cd083d23fef855e10ed43fd39ae8da9142da75d5f89fbc9ad9fed6