Malicious PDF — malware analysis report

Static analysis result for SHA-256 52dbbb31305b8887…

MALICIOUS

PDF

92.5 KB Created: 2021-09-21 23:47:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 9386dfec2236d01e9845be86f3546f6f SHA-1: b630c4a96b6f359216fd8abd42740a5cacc8ffdc SHA-256: 52dbbb31305b8887edded1cd1c271f1157413b6ec6c8493c1c8bbe779f83523a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable domains, and exhibits characteristics of a link farm. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it is designed to redirect users to malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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 http://mwcapital.net/ckfinder/userfiles/files/taseremonariledejuz.pdf In PDF document text
    • https://sukhayurveda.in/userfiles/file/35173603322.pdfIn PDF document text
    • https://granitabrasive.hu/editor_up/95991908742.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/8ce57f2568e87b7ef9282646ad346515/50295979100.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/kegegex.pdfIn PDF document text
    • http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/11641699431.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210901_5589CCACB2A93976.pdfIn PDF document text
    • http://seattlebestteriyaki.com/uploads/files/wogos.pdfIn PDF document text
    • http://sparkpro.lv/content/file/46347936685.pdfIn PDF document text
    • http://a-aqua.fr/ressource/site-image/files/11859011335.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/69908272359.pdfIn PDF document text
    • http://mastrodibaglio.it/userfiles/files/fijadix.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/muromuxadogexato.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/tilakamosoju.pdfIn PDF document text
    • http://www.galiantsolutions.com/emailimages/file/31723491887.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-09-03/images/files/fexalagesupo.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/6946389850.pdfIn PDF document text
    • http://cl-pub.com/files/files/8779370370.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/rivaranaxinufusukukoju.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/wodewatubulanijetun.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/dab035ae6e720562d7faad6e2efc119c/43352836685.pdfIn PDF document text
    • https://groupunsur3.com/contents/files/29161709437.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/20574584709.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=messages+sms+androidPDF 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_off000105a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A6 17812 bytes
SHA-256: 8ec377be05bc89199e0f1a1181d09eb509c31928b9fc1f730093e01c53bf8ac0
font_01_sfnt_off000134d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014cea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14CEA 10440 bytes
SHA-256: ad3a90bb5c04bb79bc435eac9ddc30e48234c3995509f3b7d65c48a772df2e6e