Malicious PDF — malware analysis report

Static analysis result for SHA-256 c35af7fedff9d05d…

MALICIOUS

PDF

74.5 KB Created: 2021-10-03 03:38:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 06ea156e74198ac4cd606abd42b7b4c6 SHA-1: d0abd21b056217eea3ed855abab9fc24d838f08d SHA-256: c35af7fedff9d05d1d4c8f5e21340770640b30ae1af047230c3f81953d4edbe8
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The file's structure and embedded URLs align with common tactics for distributing malicious content via PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://vidaleve.ind.br/ckfinder/userfiles/files/4734193864.pdf In PDF document text
    • http://safarang.com/basefile/files/gebixejenazesuzusedig.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/d7c7713c9a71b65fc009c537e8928271/kuzorumabofaverusoxupites.pdfIn PDF document text
    • http://mastervin.ru/files/file/15784173510.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/76303606313.pdfIn PDF document text
    • http://evergladesharvesting.com/ckfinder/userfiles/files/13695324306.pdfIn PDF document text
    • http://zoscm.zohukum.com/ckfinder/userfiles/files/52221696358.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/13808157172.pdfIn PDF document text
    • https://newsru.md/upload/userfiles/files/zuxun.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/3ec1ae86a88e3deb8ac55f5362204d87/79466401561.pdfIn PDF document text
    • http://redskap.ru/userfiles/file/lojokilebo.pdfIn PDF document text
    • http://webinaris.biz/ckfinder/userfiles/publics/files/51362543244.pdfIn PDF document text
    • http://euro-ex.com/images/blog/file/64260160700.pdfIn PDF document text
    • https://rowanmkt.com/Uploads/ckfinder/userfiles/files/22182213728.pdfIn PDF document text
    • https://impulsa.mantareys.net/uploads/plantillas/files/zuvodetuvinep.pdfIn PDF document text
    • http://pozitron-s.ru/userfiles/file/xofoduvatin.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f83550ebf5---keluwopug.pdfIn PDF document text
    • https://easternresources.net/ckfinder/userfiles/files/rokanewexikojowugamosasu.pdfIn PDF document text
    • https://rsebolivia.org/userfiles/file/69672829090.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614585f4a8061---bexamawilolejonikosakamek.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/6a4752f7c2c7d635919c936d567e67be/degek.pdfIn PDF document text
    • https://topinsolventa.ro/userfiles/file/54931041462.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=young+sheldon+a+philosophy+class+and+worms+that+can+chase+youPDF 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://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_off0000b75b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB75B 19340 bytes
SHA-256: fc6b8e51c390a85dd2aeb5d3d9811cbf27fb45b0fad4a9ea687b059e69f877fc
font_01_sfnt_off0000ea16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA16 11244 bytes
SHA-256: 2ac9d963abf61971630a861cfed02427a7abc8cd838b3e704e356607a3188f43
font_02_sfnt_off00010429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10429 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1