Malicious PDF — malware analysis report

Static analysis result for SHA-256 78c7def9660c6786…

MALICIOUS

PDF

82.8 KB Created: 2021-09-21 01:11:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4c5ee5f191355429fe3a5ce7e659ab29 SHA-1: afd76ae64823d4aac46689790229e3d02d22856e SHA-256: 78c7def9660c678610eadc8a5b90d6ea25d5141f9545781715ed73e38a5e37b9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://ketnoikienthuc.com/upload/files/49184800696.pdf In PDF document text
    • https://bevillelecomte.com/ckfinder/userfiles/files/41215441679.pdfIn PDF document text
    • http://eternoohydro.com/d/files/faxoxapafanitetada.pdfIn PDF document text
    • http://www.humillacionyestrella.org/ckfinder/userfiles/files/20208308250.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161342f1d671d9---67259905604.pdfIn PDF document text
    • http://www.drivingschool-brno.cz/files/files/80511887624.pdfIn PDF document text
    • http://netcentricnj.com/ckfinder/userfiles/files/20680253448.pdfIn PDF document text
    • http://bjqyms.com/filespath/files/20210908092232.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/mogefekinamuwasafo.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/93d6fa3d764a2d1f700c5b10eefdf93e/75616043784.pdfIn PDF document text
    • https://valerart.com/ckfinder/userfiles/files/78259536215.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/3c00646fc98d14b63687fadc482a39a2/99823676698.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/xupini.pdfIn PDF document text
    • https://fceresources.com/ckfinder/userfiles/files/fuzikal.pdfIn PDF document text
    • http://cathyourhair.nl/js/ckfinder/userfiles/files/nevirewi.pdfIn PDF document text
    • http://energy-labels.com/userfiles/file/10092043779.pdfIn PDF document text
    • http://wwm-quanta.com/upload/files/83688539976.pdfIn PDF document text
    • https://amgaa.org/temp/files/39998719532.pdfIn PDF document text
    • http://alfonsoguiggiarchitetto.it/userfiles/files/kopezolixotipezez.pdfIn PDF document text
    • http://electrogalicia.com/electrogalicia/recursos/archivos/74935500401.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/robizoritenubufegeruxo.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/jixazotosabaxakigox.pdfIn PDF document text
    • http://dreamscar.eu/userfiles/file/ragakegosonalokisoxanun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=gaming+star+apkPDF 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_off0000e086.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE086 10428 bytes
SHA-256: f9b1dfdf178935092b865ca16793ba2a3a630300d89564d2a10bf6dac8e55622
font_01_sfnt_off0000f81b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF81B 17576 bytes
SHA-256: 36cef678155075ab58e7931a33f180ea89f6002777df2e0ed97e187263ad7dda
font_02_sfnt_off0001256e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1256E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1