Malicious PDF — malware analysis report

Static analysis result for SHA-256 a58e951eb10b7bce…

MALICIOUS

PDF

83.2 KB Created: 2021-09-21 23:03:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7290b711e18d77970f88e4c437c6a317 SHA-1: 583945150d1ad91a26d44c2c4ebf2937c005bed2 SHA-256: a58e951eb10b7bced0d4322141dd899ce41eead0fcb0edac42815d4bf3d3f282
174 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple external URIs, with a high-confidence ML classifier flagging it as malicious. The 'SE_BROWSER_INSTALL_LURE' heuristic indicates the document's intent is to trick users into installing malicious software disguised as a browser update or extension. The embedded JavaScript likely facilitates this by downloading and executing a second-stage payload from one of the provided URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://medvor.ru/uplcv?utm_term=airdrop+to+android+device PDF link annotation
    • http://anninh247.info/upload/files/dararuzawivivojedifutuf.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/6817511436.pdfIn PDF document text
    • http://skontrolsengineering.com/file_media/file_image/file/sisolijolemipodax.pdfIn PDF document text
    • http://canadanur.com/resimler/files/56933104078.pdfIn PDF document text
    • https://artgallery.devctn.com/ckfinder/userfiles/files/paxupinezuzexivi.pdfIn PDF document text
    • http://ewtch.com/upload/files/39609976326.pdfIn PDF document text
    • http://ph-easycome.com/userfiles/file/karisitomukakobukuwu.pdfIn PDF document text
    • https://debo-fit.be/userfiles/file///23019976097.pdfIn PDF document text
    • http://yh-nutri.com/filespath/files/20210907024827.pdfIn PDF document text
    • http://apex-architect.ru/images/file/bujafuxafob.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/bigipisovav.pdfIn PDF document text
    • https://giolog.biz/images/bulk_images/files/fugifarewos.pdfIn PDF document text
    • http://bsp-oblspl.org/ckfinder/userfiles/files/35756829950.pdfIn PDF document text
    • https://dzido.pl/userfiles/file/xawegupeganutironovoza.pdfIn PDF document text
    • https://safrano.pl/userfiles/file/54060884810.pdfIn PDF document text
    • http://hiredriver.com/uploads/assets/files/dofazotiwem.pdfIn PDF document text
    • https://kompaspt1.com/contents/files/50804349519.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac62bf372b---25626333768.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4e41e12476d96f16186d1e6cf6a620c7/zemebe.pdfIn PDF document text
    • https://eternalbliss.net/file/mazakebut.pdfIn PDF document text
    • http://childconnect.com/swi/fckfiles/file/gegorezilelu.pdfIn PDF document text
    • https://ka-base.no/images_content/file/15033633991.pdfIn PDF document text
    • https://senesi-sklad.cz/userfiles/file/musadukibagagozul.pdfIn PDF document text
    • http://dreamcatcherltd.com/userfiles/file/zizonatosivogasitodod.pdfIn PDF document text
    • https://imad0c0.com/js/ckfinder/userfiles/files/fizidibidimab.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_off0000e011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE011 18636 bytes
SHA-256: 4ba058b84fdb2beec63e1309cece0d35479e99c83c510c6040f53b03eb168548
font_01_sfnt_off00010fea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FEA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012801.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12801 10340 bytes
SHA-256: 3eeae6d2a50cfc0a32c93a75d212f26853424f3670cd9ceb684040b7ed8f5d46