Malicious PDF — malware analysis report

Static analysis result for SHA-256 eff3ffd0323e3894…

MALICIOUS

PDF

68.4 KB Created: 2021-10-02 15:51:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 510954f0f9f2e51457119f864fb2ca6f SHA-1: 8c68e5dc4a97957452885aaf8f904197af6fc8cd SHA-256: eff3ffd0323e38942bbf80db0ae335572ed858605108596c39583f2b58a06586
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. While no scripts were explicitly extracted, the nature of the embedded URLs suggests they are intended to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://pixomot.ru/uplcv?utm_term=j+names+for+boys+and+girls PDF link annotation
    • http://tcihk.com/userfiles/rozemozolotezil.pdfIn PDF document text
    • https://www.le-domaine-de-hauterive.fr/ckfinder/userfiles/files/15346506826.pdfIn PDF document text
    • http://russkiivopros.com/images/FCKeditor/file/pidatuzilores.pdfIn PDF document text
    • https://aayams.com/userfiles/file/kolawujidolikajepumiledu.pdfIn PDF document text
    • http://importfoodfair.com/userfiles/image/2021/09/file/31494392128.pdfIn PDF document text
    • https://channeloflove.com/ckfinder/userfiles/files/wegojumudeweripuveze.pdfIn PDF document text
    • https://zapcdn.space/web/img/podborky/files/dimebemixurezuruvi.pdfIn PDF document text
    • http://www.veslovani-vsb.cz/soubory/file/bumetofosafezebaraz.pdfIn PDF document text
    • https://volandovia.it/public/fileeditor/file/89953608248.pdfIn PDF document text
    • http://eros-arena-reutlingen.de/eros/userfiles/file/29554490564.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/82436873607.pdfIn PDF document text
    • http://rhondadejean.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/99524844752.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/vifosekafot.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16151c94a21f3c---48474844665.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/12850926032.pdfIn PDF document text
    • http://spartaksedlec.cz/spartaksedlec/userfiles/file/652473829.pdfIn PDF document text
    • http://problemconsulting.com/img/download/files/40532800651.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614394e6e761c---57390883114.pdfIn PDF document text
    • https://vientangluc.com/upload/files/8101700061.pdfIn PDF document text
    • http://uralteplostroy.ru/content/file/44077847329.pdfIn PDF document text
    • https://volnynaklad.cz/data/file/20422855197.pdfIn PDF document text
    • http://kennycojewelry.com/userfiles/files/202109/1632349530.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/9634165258.pdfIn PDF document text
    • http://controldellaves.com/app/webroot/arxius/file/88952663763.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_off0000ad6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD6B 10844 bytes
SHA-256: 34fb6d9b8671c938cc8b01d2e775c425ad7c0825b9e112b4dec345bf8468ab95
font_01_sfnt_off0000c631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC631 14476 bytes
SHA-256: e41e80f9bcd8e76b2c232f17261212a5a65b507fb81a317803e834035c12c2e2
font_02_sfnt_off0000ea40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1