Malicious PDF — malware analysis report

Static analysis result for SHA-256 940a2976b8a82883…

MALICIOUS

PDF

71.7 KB Created: 2021-09-17 21:49:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fe9dfc8a9fd2be2943c0e0f7ed9676f8 SHA-1: 870451adfad7ff39c2dfde9b6d141afe04d1843c SHA-256: 940a2976b8a82883471639cf9cc3a4d2d25cb1da391d0602b5cb50e94af586e1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO manipulation to drive traffic to malicious sites. The embedded JavaScript is likely used to facilitate the redirection or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://chcial.ru/uplcv?utm_term=benefits+of+using+mobile+phones+in+schools PDF link annotation
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161347c4c65340---20927963659.pdfIn PDF document text
    • http://vdavloeren.be/userfiles/files/30405087457.pdfIn PDF document text
    • https://biocoop.legreniervert.fr/ckfinder/userfiles/files/8850350689.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jevalasa.pdfIn PDF document text
    • https://keiba-like.biz/js/ckfinder/userfiles/files/61003669856.pdfIn PDF document text
    • http://www.naturhalles.fr/fckeditor/userfiles/file/dogesa.pdfIn PDF document text
    • http://como.gattinonimondodivacanze.it/themes/userfiles/files/27532404917.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16144b157a5c92---durinaderiluvomelu.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/u46jeord5rn3fb3uinj09jgvp7/46302049058.pdfIn PDF document text
    • https://g-mtcc.com/motakamel/Ups/files/25864922769.pdfIn PDF document text
    • http://szerecsengyogyszertar.hu/editor_up/kisakipubofasobuvunusew.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/22643185246.pdfIn PDF document text
    • https://nstyapi.com/resimler/files/57753216526.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/41958471126.pdfIn PDF document text
    • http://nm-union.ru/ckfinder/userfiles/files/59239420404.pdfIn PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/41412287074.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/66144389110.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/86754286385.pdfIn PDF document text
    • http://amghanoi.com/images/ckeditor/files/51234051445.pdfIn PDF document text
    • http://theclubburger.com/uploads/files/59513473010.pdfIn PDF document text
    • http://gdgom.com/upload/file/2109091209375410039n3pk03cla9n.pdfIn PDF document text
    • http://only-svet.ru/upload/files/80136496705.pdfIn PDF document text
    • 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_off0000b8c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d0d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D8 10960 bytes
SHA-256: c68b3525f86f7ea8c2750c72cc1a84d47f8f823a06084ce65cedce17eaaee4cd
font_02_sfnt_off0000e9e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E0 15548 bytes
SHA-256: ece363553db2f0c5573f1cd8312b8163d6f9fb3d13bce93e961123b7a5dd616a