Malicious PDF — malware analysis report

Static analysis result for SHA-256 b315f18df9ce796b…

MALICIOUS

PDF

81.5 KB Created: 2021-09-21 14:59:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e8efabea1d1eccfeeb48fabd2886de9d SHA-1: 793565d311620c2a3c6560a4aba50f660fed807e SHA-256: b315f18df9ce796b35900241590fcdf316f5d29daada0cdc7ff1ce78a9df5932
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and the nature of the embedded URLs suggest an attempt to redirect the user to a malicious site, likely for credential harvesting or malware download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://led7.ru/file/remozopesipogenetodeb.pdf In PDF document text
    • http://andlupa.com/userfiles/file/93909077173.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/51129338836.pdfIn PDF document text
    • http://matrix-corporation.com/upfiles/editor/files/vabugakorel.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/bajosas.pdfIn PDF document text
    • http://naasschoolofmotoring.com/fckeditor/userfiles/file/mexuzu.pdfIn PDF document text
    • http://train-in-japan.com/images/blog/file/51946056832.pdfIn PDF document text
    • http://mebelhotel.ru/images/news/file/73196076753.pdfIn PDF document text
    • http://mariamozharova.ru/uploads/files/mojakomagev.pdfIn PDF document text
    • http://tamtamphat.com/upload/files/vubenulofejuferito.pdfIn PDF document text
    • http://geometracosentino.com/userfiles/files/demogasikokagi.pdfIn PDF document text
    • http://synphabase.ch/upload/file/pijasijumofaxuj.pdfIn PDF document text
    • http://wjcopy.com/upload/files/49670828660.pdfIn PDF document text
    • https://newsru.md/upload/userfiles/files/kerewogagobotulaxegub.pdfIn PDF document text
    • http://www.bandungmesin.com/file/salediniz.pdfIn PDF document text
    • http://xn----7sbakn3aoflleitf3m6a.xn--p1ai/userfiles/file/tokuwatazele.pdfIn PDF document text
    • https://www.hotel-restaurant-plainfaing.fr/ckfinder/userfiles/files/93634512092.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139fc163fc73---45205992710.pdfIn PDF document text
    • https://camerabentrenet.camerabentre.vn/ckfinder/userfiles/files/lunosajovifexibomirula.pdfIn PDF document text
    • https://inprovitecuador.com/ckfinder/userfiles/files/zajumaxutagotupekubopalif.pdfIn PDF document text
    • http://nextgenship.net/upload/file/20210909163115210032.pdfIn PDF document text
    • https://drisraadentalcenter.com/userfiles/file/gefafogofuti.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/38544456992.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=retroarch+android+ps3+controllerPDF 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_off0000d863.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD863 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f075.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF075 18192 bytes
SHA-256: aa78db07e8a91b093f2f2e839724849f6ccd6b301ebd9f8dfff39ebb24958fc1
font_02_sfnt_off00011fbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FBC 10828 bytes
SHA-256: e94b4efcbc7da7a33906700b23a3f472155f13348983a7fabc7ee2d5a1770884