Malicious PDF — malware analysis report

Static analysis result for SHA-256 82432d0f0b881972…

MALICIOUS

PDF

83.0 KB Created: 2021-10-13 09:30:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: dd1c4268a27804ea8bedaa76d64c873a SHA-1: 32d3fc833ba767d930b7bb9136cba68b563b0c7c SHA-256: 82432d0f0b8819729f5d56fd68cb7c3416a7b9d735bc79f767588084636c1a92
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document flagged as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and multiple links to external PDFs hosted on various domains, some of which are identified as link farms on disposable hosting. The presence of embedded JavaScript and the nature of the external links suggest an attempt to download and execute a secondary payload, likely through a social engineering lure.

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://lica.plovdivweek.com/js/ckfinder/userfiles/files/87186305453.pdf In PDF document text
    • http://a1climbing.com/userfiles/files/baluxizix.pdfIn PDF document text
    • https://www.institutvzdelavani.cz/files/60396278363.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/82a37c783d458dba8896eab92946a20f/67787726576.pdfIn PDF document text
    • https://dcimx.com/files/sisafi.pdfIn PDF document text
    • http://srtprogetti.eu/userfiles/files/tosovo.pdfIn PDF document text
    • http://belgium-ex.com/images/blog/file/95005887406.pdfIn PDF document text
    • https://vleek.com/uploads/files/17527261679.pdfIn PDF document text
    • https://www.sudoku-cool.com/ckfinder/userfiles/files/5878745834.pdfIn PDF document text
    • https://sabresources.com/FCKuploads/file/6115325771.pdfIn PDF document text
    • https://drlanda.hu/user/file/92256729226.pdfIn PDF document text
    • http://topflexsports.com/uploads/tedesovosugijun.pdfIn PDF document text
    • http://tostonet.cl/ckfinder/userfiles/files/48640469591.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/lexuveremaj.pdfIn PDF document text
    • http://ptairsupply.com/userfiles/file/runare.pdfIn PDF document text
    • http://ncdesign.it/userfiles/files/gudogalosetalez.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16141b3a9c179f---xolidegopekalafezowolufin.pdfIn PDF document text
    • https://classoft.ro/userfiles/file/fujinikadevexaw.pdfIn PDF document text
    • http://dolaninsurancetx.com/customcms/uploads/files/busitonefun.pdfIn PDF document text
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/25407210003.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/dabejumafosewafolaweduki.pdfIn PDF document text
    • http://consade.com/userfiles/file/78687579604.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/nidopezekapowijara.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/50171625810.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/tgwjJlsMqHc/uplcv?utm_term=mesothelioma+wrongful+death+lawsuitPDF 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_off0000ddcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDCB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DD 17900 bytes
SHA-256: 8df5ada4df03fac0a4240bbb0a317c84e1174015fb4232840b9c7ae06340ab2b
font_02_sfnt_off000124a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124A8 10980 bytes
SHA-256: eed983362618da19f9a5b5004941bab0fde9851a7568d30fccb152429c2681eb