Malicious PDF — malware analysis report

Static analysis result for SHA-256 a913a2bd8d6387e4…

MALICIOUS

PDF

77.3 KB Created: 2021-09-29 13:17:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fb6c2879af55dd514d899704eae4fbfc SHA-1: 9fbe8e81cd1c7e037709f962c95c54fc4efd605c SHA-256: a913a2bd8d6387e4c29c15a5cfd9d78f88ed85631475a206cd83ad58989e4e1a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is identified as a malicious PDF by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to PDF files hosted on potentially disposable domains, suggesting a link farm or phishing lure. The presence of embedded JavaScript indicates an attempt to execute code within the PDF viewer, likely to redirect the user to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://snapstudios.ca/userfiles/file/fuporijodo.pdf In PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/fpj596kcng8o1ek75p9l1nej1n/ruvimeluzoposajopugali.pdfIn PDF document text
    • https://glearningsolutions.com/userfiles/files/21221198923.pdfIn PDF document text
    • http://tunecharts.com/userfiles/file/30732726751.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/pikelevekik.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/58134064479.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.net/ckfinder/userfiles/files/82654106795.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133f7a3ad9d1---27143203893.pdfIn PDF document text
    • http://pnlestari.com/visitbali/image/files/zivizamevagevedez.pdfIn PDF document text
    • https://mimpishio2.net/contents/files/lofefuserupanuwumizuziru.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/96610831888.pdfIn PDF document text
    • http://orlickachata.cz/files/files/27702908496.pdfIn PDF document text
    • http://www.focitabor.hu/userfiles/file/birowiletoravigikip.pdfIn PDF document text
    • https://onlineadda.net/ckfinder/userfiles/files/31978621874.pdfIn PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/juzusiketogezojekenepure.pdfIn PDF document text
    • http://unseenadventure.com/userfiles/file/zidizozadixiwimadutiwojo.pdfIn PDF document text
    • http://www.iciparis.ru/ckfinder/userfiles/files/73188821774.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/15678934747.pdfIn PDF document text
    • https://shevian.com/images/file/metorosawesijila.pdfIn PDF document text
    • https://find-domain.lazy-online-shop.com/app/webroot/userfiles/files/40500205621.pdfIn PDF document text
    • https://www.bnbtravels.com/ckfinder/userfiles/files/10210822675.pdfIn PDF document text
    • https://parkerboat.hu/js/ckfinder/userfiles/files/18510154116.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=flick+kick+football+legends+modPDF 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_off0000bfe8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFE8 10928 bytes
SHA-256: 50c7dbb799671f78d4b23b5f3c1e6fb78ca7c1f8ca37435579fd320771d0e9af
font_01_sfnt_off0000d8ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF111 21464 bytes
SHA-256: ccba02f40797b014fb6a598ef9f63c7b2e6f7187afb11f2edc997c63164fedd7