Malicious PDF — malware analysis report

Static analysis result for SHA-256 085301c4b797e12d…

MALICIOUS

PDF

80.6 KB Created: 2021-09-05 04:25:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: df793191da1bf163749b7d6ed7ebb6bd SHA-1: 2a35dfac7cfa1aae3d599a06387777184bd28426 SHA-256: 085301c4b797e12dfdbd075002bd013ff27025020f63ea570de85264798c4ff4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://schodylux.pl/userfiles/file/28736958745.pdf In PDF document text
    • https://aquafilling.com/userfiles/file/fatuvul.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/fewomuxorumunadiwazujur.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/tl72pjarknf4u1cctfrqsfhgq1/62763997774.pdfIn PDF document text
    • https://kodcomputers.ro/2664/uploads/78967254194.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/16500059827.pdfIn PDF document text
    • http://sanmorales.es/userfiles/files/dogutatujosinefoniduvo.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/5f405167ef422611d80cba513b501f59/97636100630.pdfIn PDF document text
    • http://cl-metalparts.com/d/files/12194130705.pdfIn PDF document text
    • http://sb-78.ru/files/file/53736657206.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160846fe0d61de---24180811428.pdfIn PDF document text
    • https://yz-yongzhong.com/upfiles/editor/files/keburup.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2070dcfac3---kegetapam.pdfIn PDF document text
    • https://agermag.ro/mm/file/megulejazikepuxubo.pdfIn PDF document text
    • http://spoanalyze.com/wp-content/plugins/super-forms/uploads/php/files/db6180216f74ae55827ac4aec9ac3190/35796362451.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b773c3c5951---lipafapuwes.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd31d5965f---givusurajuwiwife.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/f3a6212c8be683d5492f6efda60daaec/nexobonulamuretut.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1872106df---warasezuragutiba.pdfIn PDF document text
    • https://gulceoyunlar.com/calisma2/files/uploads/7191098864.pdfIn PDF document text
    • http://paitoonbox.com/userfiles/files/95303510061.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608276250701f---21160973166.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609e7f4fee07b---lafaje.pdfIn PDF document text
    • http://machi-tomo.xyz/js/ckfinder/userfiles/files/jamiraviri.pdfIn PDF document text
    • http://superplasticizer.cn/d/files/wadivubiwo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=vmou+courses+pdfPDF 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_off0000d5e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E1 18176 bytes
SHA-256: 37d4088f0a0c9ff38e7517e9e741868e57926a9d69bb0fedf77b544393bda5b7
font_01_sfnt_off00010598.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10598 10348 bytes
SHA-256: f1d43cbf6e1c52c8517a20d1441406d669200fee6e81c6f7e81f2216ed551a6f
font_02_sfnt_off00011d00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1