Malicious PDF — malware analysis report

Static analysis result for SHA-256 efa2113f605d90e8…

MALICIOUS

PDF

80.7 KB Created: 2021-09-18 05:53:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0d49555b3300e28729b4fb7ed6ab9b23 SHA-1: c82c44995f5a53470e591e0e53a842771dbab347 SHA-256: efa2113f605d90e856e162a2b229b82c9be6aed96378566eddac20ef432f96c6
182 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains embedded JavaScript and multiple external URIs, indicating a malicious intent to redirect the user. Heuristics indicate a lure to install a browser extension or update, coupled with a visual download button, suggesting a social engineering attack. The ML classifier and ClamAV detection strongly support the malicious verdict, pointing towards a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://smidgel.ru/uplcv?utm_term=wuthering+heights+book+pdf+free+download PDF link annotation
    • https://rwd.webseo.tw/upload/files/79814364749.pdfIn PDF document text
    • https://qatarsecurityservices.com/public_html/userfiles/file/9576945384.pdfIn PDF document text
    • https://soechi.id/userfiles/file/97379392090.pdfIn PDF document text
    • http://odessawa.com/userfiles/file/labomasemoliponu.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/nipezomo.pdfIn PDF document text
    • http://pass38.com/images/contentimages/files/zanedemosefata.pdfIn PDF document text
    • http://sportingfoundation.com/uploads/file/27659497117.pdfIn PDF document text
    • http://www.bsa.by/ckfinder/userfiles/files/57752215859.pdfIn PDF document text
    • http://cgemfoco.com.br/ckfinder/userfiles/files/mimudusudakunakozexevew.pdfIn PDF document text
    • http://workcoop.org/fckeditor/userimages/file/20210911054814.pdfIn PDF document text
    • https://guruvinodji.com/Userfiles/file/33302581009.pdfIn PDF document text
    • https://bunianco.com/other_files/File/lukonulawoliwomobozavato.pdfIn PDF document text
    • https://ljlconst.com/admin/images/file/33947622185.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/1a689e0adf2cf40380127845e2e6a115/23346350737.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/16138f18c62f6c---51632809394.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/buvulakisuvupixevu.pdfIn PDF document text
    • https://dhins.com/testingsites/advantage_aviation/assets/media/file/81533481762.pdfIn PDF document text
    • https://bamfieldrental.com/userfiles/file/bedidumalosadu.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/92905530897.pdfIn PDF document text
    • http://www.ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/55247552416.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/84574225177.pdfIn PDF document text
    • http://gartenbaukoeln.de/uploads/files/45946995965.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_off0000d2d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2D2 18400 bytes
SHA-256: d6d1ff7265ae02eb6a7180cd5c96f46cbd25b8268e5990af4976d5791d49b73d
font_01_sfnt_off000102e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102E8 11188 bytes
SHA-256: c2a486a5ce507bce87d16796f30b074392a64e11012243b7a59baa68e1d908c4
font_02_sfnt_off00011cb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1