Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fcb6f32f6c0acf9…

MALICIOUS

PDF

83.3 KB Created: 2021-08-19 05:33:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4bdebae69853e89f7b177d4c4d2a5ca4 SHA-1: 637196801573e87b13689d02500f4e0f40f079e0 SHA-256: 8fcb6f32f6c0acf976ab336ca61651f7eae456c2f6fa5a29a90fc310f409d075
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ML classifiers and ClamAV, indicating it is a phishing or trojan PDF. It functions as a link farm, containing numerous URLs pointing to compromised CMS upload storage and disposable hosting, likely to distribute further malicious content. The PDF structure itself is heavily obfuscated, making detailed analysis of its direct payload difficult.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://litho-and-co.fr/ckeditor/upload/files/72110161137.pdf In PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/5791c8b3f345401a81313945e86987a9/tupejeloz.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/7f35df550d06e9e3d369b1e38de46a66/titorimem.pdfIn PDF document text
    • https://couvreur-hautdoubs.fr/internet_new/images_et_fichiers//file/tobologobulebazet.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/zofesojazefedudije.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161177afa8110b---72327937366.pdfIn PDF document text
    • http://vencedor.coop/images/admin/file/42257699934.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/zuxab.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0643bca9e5---maladebozavejamevajofagu.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/h3i59cm356sr6ku0e5mn1r2f63/83574545624.pdfIn PDF document text
    • http://hzzxtl.com/UploadFile/file/20210618190910944.pdfIn PDF document text
    • https://webupdate.ca/wp-content/plugins/super-forms/uploads/php/files/j0m6486lsjmsfh82krh1n1j38c/39039503413.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/zemutaxesupawas.pdfIn PDF document text
    • http://instandee.com/Images_upload/files/nogirevebusorewo.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/gijomududupavo.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/990fe6b49b8cd4e2660d6a0eb7a9d4f9/weburolilobuvomumotaw.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608277f52aaae---jinejorozazugefose.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608022dfcba5f---25267455988.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/wexenegixopizebo.pdfIn PDF document text
    • https://aventura-agence.lu/userfiles/files/83044980237.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/waxanodorefixenujetotofim.pdfIn PDF document text
    • http://busanpc1.com/upload/fckeditor/file/74424530670.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160815fe08f818---49833001636.pdfIn PDF document text
    • https://vieclambaohiem24h.com/upload/files/44884805675.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=bible+verse+coloring+sheets+printablePDF 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_off0000e2bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2BB 10912 bytes
SHA-256: f39bb9308df5d57a8d6c27c205982c46dc75378070433ba8a1fd99bac8ef5c29
font_01_sfnt_off0000fbc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBC0 16852 bytes
SHA-256: 185c758f593b5d7b73be4b2d5533bb6467fc863274dccda52c464d1d851d4519
font_02_sfnt_off00012785.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12785 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1