Malicious PDF — malware analysis report

Static analysis result for SHA-256 c91c396ae8ef5a3d…

MALICIOUS

PDF

93.7 KB Created: 2021-06-27 15:59:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d884b914b001d7d338fcf3e9cc3478a SHA-1: ff5aca916cd145574a7d7adf9113a920db359d47 SHA-256: c91c396ae8ef5a3ddfcbb32d1c3ff5129f4efc6818ed81489b1c7a4fd673318d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. Heuristics indicate this is a link farm, with a high ML score and ClamAV detection confirming maliciousness. The URLs likely lead to phishing pages or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/09egbid37p6igk5k45t3j2r6e5/nunawom.pdf
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8b898de25---74233764845.pdf
    • http://alexhofford.com/temp/files/file/weduwomorugovafusogutepi.pdf
    • https://pjkconstruction.ca/images/file/porigajapus.pdf
    • http://vervesimuhub.com/userfiles/file/notomorudasamuvoxupa.pdf
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/23jut7cum7ekv010f3244tghad/12473868357.pdf
    • https://peilimineko.com/userfiles/file/40881667576.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/557383d02374bc9473b9c806c316f73c/4763179292.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/28a869c2064635ec1031258c874a569f/fokupu.pdf
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d8c725be7---vupupobutaledexowosijev.pdf
    • http://zpb-maciejewski.pl/upload/fck/file/nudejuvu.pdf
    • http://www.look4job.gr/images/_user_na/file/41965067773.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/a9ba0c0856c50d77cfc836934a9c89c4/poxavejezi.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f125e434f9---15776280341.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b89cc69c37---wugubumik.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/2a0d9753d68b87d6c42d47447be585de/jowivezudal.pdf
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a8ec1752bae---komobugewanunafeg.pdf
    • http://danieldesignpro.com/userfiles/59860621470.pdf
    • http://leilehua76.com/clients/4/4d/4d80c013f15dbe3c797666a457780dca/File/vemes.pdf
    • https://soechi.net/userfiles/file/8817380757.pdf
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/jfpt9tkmo220k1q4f2nn074ijc/wujalosezugerukupe.pdf
    • http://imaginove.eu/data/Files/31329961654.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/jlk28o38r7shs77360tqkvf60l/monimexajoja.pdf
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ced300d290---vuzojejufore.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16094170ebf3ff---5052983896.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=financial+creditor+and+operational+creditor
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000109d9.bin
ee0f337d0e919f5bdb07d88c86a2ae25b120618dd6ef2965d32cae91c25cc6d6
pdf-font-stream PDF embedded font (sfnt) at offset 0x109D9 18244 bytes
font_01_sfnt_off000139f9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x139F9 16792 bytes
font_02_sfnt_off00015210.bin
997d30bd8fcc0a79728ccc519d8405b3e8f46c20344e8781c64c42829b188105
pdf-font-stream PDF embedded font (sfnt) at offset 0x15210 10316 bytes