Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef78c617b92bfba4…

MALICIOUS

PDF

71.2 KB Created: 2021-09-26 16:15:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: dd8ac902672dc4da7926068e69872ee6 SHA-1: ea374f27ccc764df603a92da29207e5cc173c8e0 SHA-256: ef78c617b92bfba444d284a9e72f1a0ca86ce45235c164ead080ed06fd39f5a3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with many pointing to disposable hosting and exhibiting link farm characteristics. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://chcial.ru/uplcv?utm_term=how+to+install+ubuntu+in+android+phones PDF link annotation
    • https://prestinieurope.com/userfiles/files/84651066618.pdfIn PDF document text
    • http://flyingkirin.com/uploadfiles/file/081848343775.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136d665985dc---vugesuzevo.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/43392676261.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/26039816020.pdfIn PDF document text
    • https://www.gurgy.net/ckfinder/userfiles/files/melurivemuso.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/37787127978.pdfIn PDF document text
    • http://trunglam.vn/uploads/userfiles/file/20193693129.pdfIn PDF document text
    • https://olivierdaulte.com/ckfinder/userfiles/files/tatajenawuju.pdfIn PDF document text
    • http://ke-sen.com/userfiles/file/1632029791.pdfIn PDF document text
    • http://ymmicro.com/files/files/teterawuwudelewukudotuvex.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/71157725517.pdfIn PDF document text
    • https://shivajigrihnirman.com/singhania/downloads/file/wefifetixe.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16134d67a56f50---naduba.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/96421707069.pdfIn PDF document text
    • http://bangtaisay.com/uploads/userfiles/file/sojomaxemok.pdfIn PDF document text
    • http://techbis.pl/files/file/5110145296.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/75407534668.pdfIn PDF document text
    • https://jajugroup.com/ckfinder/userfiles/files/bazokoxeke.pdfIn PDF document text
    • http://mojaksiegowa.net/userfiles/file/juduna.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/ckfinder/userfiles/files/gakisutumoxeva.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/2c7190fc91a15e736f6dd62f0d6cb73e/powanobesejujufigisom.pdfIn PDF document text
    • http://beautybybelief.com/admin/images/file/wisifigadaxunorokuxodazal.pdfIn PDF document text
    • http://ecole.ru/text/images/file/julubuzujerebuvuvimowori.pdfIn PDF document text
    • http://folientastaturen.pl/_data/file/56034140958.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_off0000b393.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB393 15880 bytes
SHA-256: ff2b3d790974da183a02a27435d18bd1e998cc6e16369b0f1d007910e7d94919
font_01_sfnt_off0000dc3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f451.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF451 10808 bytes
SHA-256: 52de37ffc6d26c87a1fa8ed792d66497f9400cacce196ed804977e29370ff240