Malicious PDF — malware analysis report

Static analysis result for SHA-256 19a43bad05f7b60d…

MALICIOUS

PDF

94.9 KB Created: 2021-08-30 13:49:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f22b5169c15b377ae6064aa4c3c3c7cc SHA-1: 64f42abf33829783e82729f1b933e8ee04501b11 SHA-256: 19a43bad05f7b60da16875dbadb901f469b0dc7bf6b7dc986e3e874f779716d7
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • 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.
  • 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 http://guss-ex.de/uploads/fck/file/26691926963.pdf In PDF document text
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/ab1ac7b56f90d78a173964f1b84391bf/43062064452.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/ji1jqg6gav4og5flv4ru9m7ls6/98590723176.pdfIn PDF document text
    • http://yaeram.com/userData/board/file/14020926786.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5d37c79d3---55392547450.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/47326489709.pdfIn PDF document text
    • http://nmglyxx.com/userfiles/file/5736523887.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/q4i0gk66s61633vn8vde8viokf/judulizuse.pdfIn PDF document text
    • https://tylbm.com/Upload/ckeditor/files/70342562104.pdfIn PDF document text
    • http://viorina-deko.com/images/file/72916014675.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160795a56c1d0d---fowivipozol.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf47e9413c---toxapevesi.pdfIn PDF document text
    • https://penzionradvanice.cz/res/file/gimazizaximejoso.pdfIn PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/sizaguboweda.pdfIn PDF document text
    • http://kiemdinhcan.com/Images_upload/files/fitewowemididu.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7edf72bc01---50002118613.pdfIn PDF document text
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/8f0512bb38a4d09bc44423865973660d/tasafenalenutezo.pdfIn PDF document text
    • http://cpils.com/userfiles/file/10599513429.pdfIn PDF document text
    • https://ahha.az/userfiles/file/nogolinodulejapivojopevam.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16079d070083fb---zaxekevasugifobumolu.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/a12c3cd2ed25dc1b2814e76f82b911db/senafarifagikagabawadetij.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f70fe46e66f---19169406978.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a04f2312a9f---xudenifeduxifuwagavo.pdfIn PDF document text
    • https://quangcaoxetaxi.vn/upload/fck/file/vezile.pdfIn PDF document text
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/53f8a52070716c6bb1a901963c6fd88b/mexixe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+find+no+of+atoms+in+a+compoundPDF 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_off00010bfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BFC 18500 bytes
SHA-256: 0994d59baac22ae0571918ffa9ffa541464dc085863c875cfee12d0948d4e315
font_01_sfnt_off00013c9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C9E 10680 bytes
SHA-256: a53492dbbb862d2d0c2d9d49139695a809c6546c2880b8eb18bb226f28821991
font_02_sfnt_off00015523.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15523 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1