Malicious PDF — malware analysis report

Static analysis result for SHA-256 d85a0147868a2013…

MALICIOUS

PDF

83.9 KB Created: 2021-09-09 16:29:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: bed954e2dbfbd18e824ca2cce59bba6c SHA-1: 0b8de70c8f170e747c9b9663f2f9bf4538fab426 SHA-256: d85a0147868a201339c72adc5da82c911762872fb0160e36fc42ada11d720706
174 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV and a machine learning classifier as malicious. It contains embedded JavaScript and displays a fake CAPTCHA, a common lure to trick users into clicking external links. The document body is heavily obfuscated, but the presence of a fake CAPTCHA heuristic strongly suggests a phishing or malware distribution attempt. The embedded JavaScript and external links are likely used to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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 http://radiopoint.cz/userfiles/file/xojewamoto.pdf In PDF document text
    • https://rugsinc.in/UserFiles/files/69164685798.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/xobezegovinobawuxi.pdfIn PDF document text
    • http://nitexprofi.cz/userfiles/file/fuwox.pdfIn PDF document text
    • https://irantruck.ir/data/file/fejadukokuvudagu.pdfIn PDF document text
    • https://regaluxiluminacion.com/uploads/assets/file/dilaxasizeriwiperesezile.pdfIn PDF document text
    • http://knupress.com/pds/editor/file/14360418537.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/wufenafivevisoviwetuv.pdfIn PDF document text
    • http://serviphony.com/tinymce/jscripts/tiny_mce/plugins/phpimage/phpimage/upload/images/file/88187544575.pdfIn PDF document text
    • http://drcleancenter.com/uploads/files/202109050255057811.pdfIn PDF document text
    • https://pmfegypt.com/userfiles/files/nakononarufemowurajabejix.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/35621175413.pdfIn PDF document text
    • http://turystyka.powiatlubartowski.pl/admin/ckfinder/userfiles/files/mutil.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/rugaruvizovu.pdfIn PDF document text
    • http://toyotaprius-custom.com/js/upload/files/92581139158.pdfIn PDF document text
    • http://hejia-ele.net/upload/sibegixo.pdfIn PDF document text
    • https://vivaldiroberto.com/img/files/mediafiles/file/lupolifawogodo.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/bimomofepemajogofumupito.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d62527354---pozoresazexizakaza.pdfIn PDF document text
    • http://umbabox.com/userfiles/file/85288184581.pdfIn PDF document text
    • http://podlahyadvere.sk/editor_uploads/system/files/sedowasivajigaxuzuvobi.pdfIn PDF document text
    • http://liburnia.pl/userfiles/file/xudeduzif.pdfIn PDF document text
    • http://sk-uralstroy.ru/uploads/files/46222809499.pdfIn PDF document text
    • http://bloodfaces.de/attachment/file/favekuka.pdfIn PDF document text
    • http://christopherdallo.com/file/ziwabipubitijapupexe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=attack+on+titan+2+download+apkPDF 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_off0000e36d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE36D 10384 bytes
SHA-256: 9ab7ca8ed41859377777ddbc2111d12fc130287b75550ad42ec41def5c307bbc
font_01_sfnt_off0000fb2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB2F 17724 bytes
SHA-256: 5e632ae368b7007bdaa043e89aca80fa5a2eae1cf3056d1edc1e49829d7c8b11
font_02_sfnt_off00012953.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12953 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1