Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9cc3c853812de6f…

MALICIOUS

PDF

73.4 KB Created: 2021-09-08 06:00:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5f0a963a25bf7e6ac5217bfca2c9d3a1 SHA-1: 07d51dc4000dfe0be85893c36df9a4d7b495844f SHA-256: d9cc3c853812de6f634875b1add5839699c361acc4f15fbb816c801aacc9dbe8
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV detecting it as a phishing trojan. It contains numerous links pointing to compromised WordPress sites and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for human readability but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://crysiq.ru/uplcv?utm_term=japanese+parallel+text+pdf PDF link annotation
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa08a16932e---7052538287.pdfIn PDF document text
    • http://jtipartner.com/ckfinder/userfiles/files/4975318690.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/46864219072.pdfIn PDF document text
    • http://to-tuong.com/media/ckfinder/files/mezedofotazi.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/3e347935fdabb4bd91e73ea600654aa4/vevimubewagunexosu.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/1580116096385421b288a9a34a4a1cbb/xefar.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/994537b3de1b68357bb5a4a1eaffb16e/13635178657.pdfIn PDF document text
    • http://giustizianuova.it/userfiles/file/bisuzokakixilazerojarol.pdfIn PDF document text
    • https://actorconseil.com/files/file/48224604521.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b8ae530d6e---nezisofus.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/7f08cd5bd25cb13e86c5a2ef1b67a60c/nibozurodozoxo.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/ki0n3m785se3vlpbf9spruvrij/37519322519.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/towudibezefisoku.pdfIn PDF document text
    • http://taeguektour.com/FileData/ckfinder/files/20210904_270C4D6CFCA8714F.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609e237a4a2ed---zokenazutoponutir.pdfIn PDF document text
    • http://leicesterbiketec.com/userfiles/file/bekuwuzazibavegukojikexew.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/tamumuforatodugawu.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/ltgamtulpgqlfk662gs9caionj/simuzerugigupuku.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/b314ffe9b65d6fdf2389c989162f483f/1826290470.pdfIn PDF document text
    • http://kystar.net/filespath/files/20210817043237.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608990736de5d---88820079289.pdfIn PDF document text
    • http://panda-es.tokyo/yamituki-n/uploads/files/dutebelurosawap.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_off0000be49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE49 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d660.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD660 10372 bytes
SHA-256: 86d6cbc3cf4f2ed3c9f86da997384acc3da067e9066b2999668115fa27546535
font_02_sfnt_off0000edfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDFD 16488 bytes
SHA-256: 7c22a0c2bdecabf31e568d35da3dbd54c48b7bddde5fd4485d919b196db6ba0b