Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d36db7c6b365372…

MALICIOUS

PDF

81.2 KB Created: 2021-09-18 04:54:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 22d654ea2fbb00deb8621ccfacc4e304 SHA-1: 67ca65f93499d0b415685821f4b19c371c2114d5 SHA-256: 7d36db7c6b365372ba3df304ce7076b268cba6ed078e1914536716573517b165
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://synerhu.ru/uplcv?utm_term=vertex+equation+calculator PDF link annotation
    • http://gaia-onlus.org/userfiles/file/60206733000.pdfIn PDF document text
    • http://pnmanagementsolutions.in/uploads/76879586305.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/58624924083.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/35422451844.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161393d1b21298---62483376374.pdfIn PDF document text
    • http://vpecargo.com/userfiles/file/54169939860.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/uus8b6qota097fu46oc38qgc92/mukazipezenexafejizezusa.pdfIn PDF document text
    • http://fred-robin.com/ckfinder/userfiles/files/21782802123.pdfIn PDF document text
    • http://fourfoods.com/images/files/87255021717.pdfIn PDF document text
    • http://debsecond.net/UserFiles/File/86285176928.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109061150402429.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/57837447760.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/80640099547.pdfIn PDF document text
    • https://lmcmanager.com/ckfinder/userfiles/files/93286216948.pdfIn PDF document text
    • http://platcometals.com/images/file/giridemugepofujepodep.pdfIn PDF document text
    • http://cateringkieuan.com/uploads/userfiles/file/wesufikisobukajasitot.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6e38883ef---65681906196.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/161415c7271e78---5328077936.pdfIn PDF document text
    • http://www.dgtrans.co.th/login/ckfinder/userfiles/files/24763237999.pdfIn PDF document text
    • http://rc-saty.cz/gais/image/file/zolaxatorufidaxogifekuk.pdfIn PDF document text
    • http://htwy.com/upload/file/25078683486.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/50378710302.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/b5cgdiekekt5dc3u5u8jdccdj7/rutodu.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_off0000d9df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F1 17532 bytes
SHA-256: e5d5ac7bcf1ab923e4c25fc09a32da3eaa5cf64073435343090dd3248059529f
font_02_sfnt_off00011f96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F96 10372 bytes
SHA-256: 29f7ea223eb4c88ade82fbeb698c4f9ec9a338ae80ecf620c7ddda0bc4ea2941