Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce81236ba0c5334e…

MALICIOUS

PDF

74.7 KB Created: 2021-10-05 00:13:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 1c41fcf77fa5833f2f564dafb8748734 SHA-1: e2f57d61e703ca7f74c4d024e2b65871c7f73706 SHA-256: ce81236ba0c5334e095d74e8aba049d8665f5202003814c157373ecdde4a8895
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting a phishing or malware distribution attempt. While no scripts were explicitly extracted, the PDF structure and link farm indicate an attempt to lure users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://euinsuti.ro/app/webroot/files/userfiles/files/94738188912.pdf In PDF document text
    • http://ty-int.com/files/files/nipakadilosimed.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/43299125325.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/797e4ae59d95e41d53cf0d702419da4d/jerimimemilolirasolubakem.pdfIn PDF document text
    • https://www.drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16148f79e66b07---56563102055.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/ad395bcf09fd3f46e8db2f463932de80/jasadixoxukemobuvum.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/pavamomedup.pdfIn PDF document text
    • https://korankertas.com/contents/files/tuvodup.pdfIn PDF document text
    • http://safedoorsystems.com/cmsimages/file/bezax.pdfIn PDF document text
    • https://rocha.pt/userfiles/file/48415142160.pdfIn PDF document text
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/vapuwasajimubabomos.pdfIn PDF document text
    • http://elfobchod.cz/foto/Image/file/23917452967.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/fufunapetapepebidav.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/77743019955.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1615668a485d14---9415615080.pdfIn PDF document text
    • https://sunarchegypt.com/userfiles/file/74219852195.pdfIn PDF document text
    • http://prosefkuchare.cz/userfiles/jalipisinijamevajewegixa.pdfIn PDF document text
    • http://life-worldwide.org/assets/uploads/files/nogil.pdfIn PDF document text
    • http://beauty214.com/uploads/files/202109121355503525.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/egltudckkmtk0u6v3e0b1pqb0a/9353025651.pdfIn PDF document text
    • http://tradotel-riviera.com/file/14030367963.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16131bab5b5154---suzibinomev.pdfIn PDF document text
    • http://addon-colsman.somantec.net/ckfinder/userfiles/files/genoxegamo.pdfIn PDF document text
    • http://letsfinal.com/userfiles/file/72310523573.pdfIn PDF document text
    • http://devveb.net/userfiles/file/4312949139.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+can+stew+meatPDF 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_off0000c483.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC483 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC9A 10232 bytes
SHA-256: 1e2afad6327c81381513ebcb0deab5a3f283e412199c48657e7faeb21880e595
font_02_sfnt_off0000f398.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF398 16340 bytes
SHA-256: 582277c287ec1ce50d7d7f794b5beb7ccc806465474da533aad5b05af7f7f445