Malicious PDF — malware analysis report

Static analysis result for SHA-256 8204c90d7ce2e0f6…

MALICIOUS

PDF

70.1 KB Created: 2021-09-26 10:14:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ff6c04253f70dd2d88ef43c371b0679e SHA-1: 0c9a5a72bc408d13789b9f9aec81cdfb79074d16 SHA-256: 8204c90d7ce2e0f6aea143674272e5dfb4f0d0e21b9d9917471c6b7fc84c3c3a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to various PDF files hosted on potentially compromised or disposable domains, suggesting an attempt to obscure the final malicious destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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 https://perfecthospital.org/ckfinder/userfiles/files/76421702293.pdf In PDF document text
    • https://www.pu-sk.com/app/templates/js/ckfinder/userfiles/files/94316072398.pdfIn PDF document text
    • http://footstepfloor.com/upfiles/files/6914588802.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613af8e971d9f---soxolimej.pdfIn PDF document text
    • http://infiniti.e-library.tw/uploads/files/17536138836.pdfIn PDF document text
    • http://www.madiran-cruduparadis.fr/ckfinder/userfiles/files/xudowefexetanoxalavev.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614b35fee0189---58717656376.pdfIn PDF document text
    • http://ls12368.com/userfiles/file/47321181044.pdfIn PDF document text
    • http://autoneza.cz/UserFiles/File/bovuxemezuxid.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/a7f845cd779bdb2391ecf343268c1e28/sagubi.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/vuxipesexugobuxusufun.pdfIn PDF document text
    • https://tomas-music.com/contents/files/mudoze.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/wamaxibixirotaximi.pdfIn PDF document text
    • http://phutungvespaco.com/luutru/files/vorupodoxefavoxevejexi.pdfIn PDF document text
    • https://autohausnschmidt.de/userfiles/file/27176406256.pdfIn PDF document text
    • https://bnovum.hu/downloads/82479938948.pdfIn PDF document text
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/zumakawutenatadizasipu.pdfIn PDF document text
    • http://videlec.be/ressource/file/7795329174.pdfIn PDF document text
    • http://deauville.ru/files/file/vuxakuwegarif.pdfIn PDF document text
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/46082100299.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/pokuzuwepe.pdfIn PDF document text
    • http://saeronbio.com/userData/board/file/lupazij.pdfIn PDF document text
    • http://jutaek.humenia.com/upload/userfiles/2021/09/files/210918004627.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/53k9k1v5973mmt89rulfatdim2/duwusulovifodapilofene.pdfIn PDF document text
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lakituwokuw.pdfIn PDF document text
    • http://www.atsamuihaus.com/image/upload/File/29608745590.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=best+emulator+for+low+end+pc+downloadPDF 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_off0000b24b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB24B 15280 bytes
SHA-256: 81e1fd491adc5427bd4607c1bee40e5b052406471192f86d13d99464378d8a3b
font_01_sfnt_off0000d925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD925 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f13c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF13C 10928 bytes
SHA-256: 23f822004754272176d162c11002cc524121ac0524fc2b45ed46124e9ac3f486