Malicious PDF — malware analysis report

Static analysis result for SHA-256 a45fc9f4a8c39311…

MALICIOUS

PDF

73.9 KB Created: 2021-09-06 21:55:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 37baffc5d3a0a00770787bec412a8d3a SHA-1: 7a582f3a8bd5f35e1f45e3eade178559520d71f9 SHA-256: a45fc9f4a8c3931109672ecca27c614a5d841c6cd595cf5d77d2ffd57da1370e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm or phishing lure. The presence of embedded URLs and the nature of the heuristics point towards an attempt to redirect users to malicious sites for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

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://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/71be493acfed74e3ec4ac2354b92bfd0/73707269269.pdf In PDF document text
    • http://raylutickenterprises.com/userfiles/files/18342877196.pdfIn PDF document text
    • http://yilip.net/userData/board/file/20251385826.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/9c8cc2fedf7ccd79da6b901b4d4e2c94/bijural.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/80217318028.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/walufodevadorikan.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/86e4127e2b1e5edb756c567d05cad399/59995172433.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/rezoduvilerojurubewivagiw.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/59190935684.pdfIn PDF document text
    • https://elminhaj.org/userfiles/file/25935919723.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1ac7f01c76---sapefibumomumodiburiso.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/e7484012b5a0c0f87e3140f935ca068e/92775370183.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/61998305089.pdfIn PDF document text
    • http://lumieretvie.com/userfiles/file/regakiwodi.pdfIn PDF document text
    • http://slp70.com/clients/873855/File/94865105005.pdfIn PDF document text
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/2i3s8at49n9vdnp5p66gohj6ou/rukaretasemanokujutu.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a42786185cc---60472326525.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160862d3ee3940---tilazamev.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/bevafana.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/2i091h1elk0kntds2od0q8sjs9/gupuzezexivifolawitema.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/161260b7b0ad44---bejonufodemofog.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3f86857e9d---96251291753.pdfIn PDF document text
    • https://szabobuszrendeles.hu/files/files/95354986858.pdfIn PDF document text
    • https://nestsearch.in/admin/uploads/file/zuzedegafumelupikogoro.pdfIn PDF document text
    • http://soldresold.com/Shradhdha-Mehra/soldresold/final/ckeditorimage/files/lumadifewupumige.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/bgu44efv873cefkin5612lu1i6/paxobekilexonaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=propiedades+de+aldehidos+y+cetonas+pdfPDF 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_off0000bda5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDA5 16860 bytes
SHA-256: df1d567b5bf961224a50c5c0d814550d0dc1b3befef50d2d49360d9aaa8061c2
font_01_sfnt_off0000e85d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE85D 10832 bytes
SHA-256: 53ab8cce8427701b1cdb8d12b16594fcef6b41adea94f826fd9a1cb63bb89db2
font_02_sfnt_off0001014e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1014E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1