Malicious PDF — malware analysis report

Static analysis result for SHA-256 087f5e25f10cfb31…

MALICIOUS

PDF

85.2 KB Created: 2021-09-17 08:48:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0fe8a5624a1170d587575da83cd4a612 SHA-1: d65deccebd58a7a0bcad64956824996761c94afb SHA-256: 087f5e25f10cfb314d7bc49f21e13236d055c02c35257b95576047814f38ad53
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged as malicious by ClamAV and an ML classifier. It contains an embedded JavaScript stream and a large number of external URIs, many of which point to disposable domains. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm strategy, suggesting the document's primary purpose is to redirect users to potentially malicious sites. The embedded JavaScript may be used to further exploit the user or download additional payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • 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://huntic.ru/uplcv?utm_term=redmi+note+3+lineage+os PDF link annotation
    • https://shoppingplanet.ro/ckfinder/userfiles/files/velinekolumobixemu.pdfIn PDF document text
    • http://xatrbio.com/userfiles/file/nuvodowemeximubuxefe.pdfIn PDF document text
    • https://noriupapildu.lt/ckfinder/userfiles/files/39764844680.pdfIn PDF document text
    • https://pcetravel.com/files/file/97771762825.pdfIn PDF document text
    • http://dailycan.com/userfiles/files/5658334478.pdfIn PDF document text
    • https://www.algeos.com/js/ckfinder/userfiles/files/demapuvuxupunu.pdfIn PDF document text
    • https://dpt-mh.com/uploads/news/files/bakujikidiluliduluvudegal.pdfIn PDF document text
    • https://cochleartudaskozpont.hu/files/31555917551.pdfIn PDF document text
    • http://becskeicsodajo.hu/admin/fck_upload/file/felupugotumivij.pdfIn PDF document text
    • https://ontogepszerviz.hu/editor_up/99204167438.pdfIn PDF document text
    • http://remproekt-m.ru/admin/ckfinder/userfiles/files/tekikiresivatifitezopukuw.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/ada8cd42f62c974b064243827142ca79/sezofogef.pdfIn PDF document text
    • https://tsydesign.com/userfiles/jws/files/21034210777.pdfIn PDF document text
    • http://hotelalbicia.com/userfiles/file/67107736862.pdfIn PDF document text
    • https://alwaysthesame.pt/site/upload/file/tuxadupopopepufukujidin.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/labutojajazufaxazob.pdfIn PDF document text
    • https://www.l-games.jp/js/ckfinder/userfiles/files/69258359804.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/46171824734.pdfIn PDF document text
    • https://kimansion.com/uploads/file/59056110969.pdfIn PDF document text
    • https://bliznacite.com/files/dekelasogifim.pdfIn PDF document text
    • http://hondaototanan.com/upload/files/towivodu.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/zapejikofixepuguga.pdfIn PDF document text
    • http://bolshunoff.ru/images/wysiwyg/file/38260914403.pdfIn PDF document text
    • https://rubyyadav.com/nbloom/fckuploads/file/65321433176.pdfIn PDF document text
    • http://puisan.ru/uploads/file/bikodur.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_off0000e6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CE 18384 bytes
SHA-256: 330bdcbae9b258f359c0c3183eddbbc2e0b92e5c516cd0fed9d3645723a1731d
font_01_sfnt_off00011648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11648 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E5F 10708 bytes
SHA-256: 9c5baabafffb0bef9bb047e7345da079ea780f5d4d56e2a5f48b903290ac1730