Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cbdef9c3457f05b…

MALICIOUS

PDF

68.8 KB Created: 2021-09-26 13:54:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 55ec07e6b2b23e9f5ad2a68c143c8049 SHA-1: 330a4b485dc36c79757b838d40d96caab0a0a22a SHA-256: 9cbdef9c3457f05b78e61e8017b24d16d8c7dc893cf449ee6bef22388dd3bb46
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting a link farm or redirection mechanism. The presence of PDF-specific heuristics like 'PDF_URI' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the attack pattern of luring users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://inwebjor.ru/uplcv?utm_term=screen+mirroring+android+ps4 PDF link annotation
    • http://design-klasse.de/ckfinder/userfiles/files/vogigumitejid.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/korudagalifarojedituru.pdfIn PDF document text
    • http://nickelsgrafikdesign.de/ckfinder/userfiles/files/57840940910.pdfIn PDF document text
    • http://cobmedia.hu/include/xiberewanad.pdfIn PDF document text
    • https://magyar-logyogyasz.hu/fileok/file/lugegotazunidar.pdfIn PDF document text
    • http://gallery4walls.com/upload/editer/file/83979925819.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613509cac107e---tutikisog.pdfIn PDF document text
    • http://redskap.ru/userfiles/file/gomazivilitorevit.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/19342906873.pdfIn PDF document text
    • http://melodylavernebettencourt.com/media/file/pemutiwonopefudadolixabex.pdfIn PDF document text
    • https://danielfelber.ch/userfiles/file/64809504777.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/lodededoloram.pdfIn PDF document text
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/faxipafopij.pdfIn PDF document text
    • https://bepxuyenviet.com/upload/files/36321756433.pdfIn PDF document text
    • http://gwtcs.org/Content/uploads/files/lagotuko.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/s2trvdlogeclfb7lgjmm18js22/tetirararuvobosep.pdfIn PDF document text
    • http://tksvolga.ru/userfiles/file/dubudonurej.pdfIn PDF document text
    • http://sterenstein.ru/userfiles/file/24936752637.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/wawen.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133aa479d1e0---vepoz.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/a7662ef1b2c32f49e48b4d633abe1f8e/7005839731.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/654d10ea1de7b0ade0858e80792789eb/14129827742.pdfIn 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://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_off0000b011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB011 14704 bytes
SHA-256: d7c16c494666ff12db0d9a5f87916316a87d2cac13a752d9de4a3abd471a3c4b
font_01_sfnt_off0000d4b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eccb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECCB 10868 bytes
SHA-256: fe18e032b265c41f91bc39b30cf2b359b97f90d73a7672221cc84983018fad72