Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac62f611a5e0a4ea…

MALICIOUS

PDF

76.6 KB Created: 2021-09-17 12:15:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0a8ad9b2938ce98b3a4de7f1ad0ac1cd SHA-1: 8797be0b430f5aea32e7b8a548fc197da8fc2131 SHA-256: ac62f611a5e0a4ea1191951c0fbd50e495926ec0ae9e9479db0bf3737775ff2a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristic analysis identified it as a link farm on disposable hosting, with numerous links pointing to PDF files, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/90c8f7f222a2bb6c38a73e7fd3a72ee5/47317164531.pdf In PDF document text
    • http://elsped.hu/files/file/furalelarovomuvunim.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/vapomedosisebikitasi.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/narabiwubotajugasebef.pdfIn PDF document text
    • http://studioingegneramato.com/userfiles/files/79428039629.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210912_AA0D0D1496B17094.pdfIn PDF document text
    • http://jmlukanich.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50935117777.pdfIn PDF document text
    • http://ziguratex.com/helpdesk/app/webroot/img/userfiles/files/20207099524.pdfIn PDF document text
    • https://trisyscom.com/userfiles/file/morejigafev.pdfIn PDF document text
    • https://quizai.com/uploads/files/21917370659.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/mokatadakigenotexidi.pdfIn PDF document text
    • http://lehnerkom.de/images/uploaded/file/97065659898.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/fajirotelasutodokezamoju.pdfIn PDF document text
    • https://durimawar.com/contents/files/merirukuxux.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/gijedufak.pdfIn PDF document text
    • https://artinterior.bg/userfiles/file/lilubelitop.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/ximumisakube.pdfIn PDF document text
    • https://shatalarab-llc.net/userfiles/files/kawizovaf.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/161418cf3123ed---36496629328.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/giforapikafeje.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/tazojonanojoda.pdfIn PDF document text
    • http://thedreams.cz/files/98943090030.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.com/ckfinder/userfiles/files/sitajurefumusirote.pdfIn PDF document text
    • https://buyafranchise.org/files/files/jomurugovakevofedog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=pdf+to+word+best+converter+freePDF 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_off0000c8ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e0fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0FE 16884 bytes
SHA-256: bd0e40e33317881648aac61443f213ebcee9ab0b31f3aab007ee5abd7bdc1e22
font_02_sfnt_off00010c8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C8D 10460 bytes
SHA-256: d211ac4d6ad01919480309750930ef592cba0dbbb15eba4c0dd4cc01b806fff5