Malicious PDF — malware analysis report

Static analysis result for SHA-256 8799403a8f23a951…

MALICIOUS

PDF

81.6 KB Created: 2021-10-12 05:35:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: c42758927e93361ead51c079fe6dfb9e SHA-1: b464eb50bad5bbe25e2793f53a3b0a7a2afbf079 SHA-256: 8799403a8f23a951c82133115ecf33a4eb720c86581a68f0cbf21d11975cfc7c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many of which point to compromised websites or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing sites or download further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • 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.
  • 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://ban-mat-canh-kinh.theonejsc.com/userfiles/file/reluludegete.pdf In PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131cefc69f4e---17635389353.pdfIn PDF document text
    • http://tuivaivietnam.com/uploads/files/nojovinaxuluxufa.pdfIn PDF document text
    • http://industra.sk/userfiles/file/zatedepapudotomajogeno.pdfIn PDF document text
    • http://primeasset.hu/fileok/file/zorutufadem.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143213d0f8c9---wudomokupelumitiku.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/81892052148.pdfIn PDF document text
    • http://logtech.cz/foto/Image/file/55164848259.pdfIn PDF document text
    • http://straps.by/ckfinder/userfiles/files/39130030346.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e13c5d4e9---71908859469.pdfIn PDF document text
    • http://briquettemachinery.com/d/files/rodod.pdfIn PDF document text
    • https://showdetango.com/bafa/userfiles/file/rerozobuxujiduk.pdfIn PDF document text
    • http://shinaval.ru/userfiles/file/revigexetajasa.pdfIn PDF document text
    • https://hfbee.tw/upload/ckfinder_temp/files/20210914103332.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1615b215ec454b---soburorur.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/68256675362.pdfIn PDF document text
    • https://bedandbreakfastchia.it/userfiles/file/xotufesemaz.pdfIn PDF document text
    • https://securitydm.net/slicice/file/jelapisovu.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161480fc9ed1cc---puvise.pdfIn PDF document text
    • https://dogathermalhotel.com/resimler/files/53183926194.pdfIn PDF document text
    • https://tecnomatec.cl/upload/file/48258374573.pdfIn PDF document text
    • http://africalegal.nl/userfiles/file/safono.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/6Zflnl449io/uplcv?utm_term=income+tax+calculator+new+regime+excelPDF 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_off0000da3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA3D 10644 bytes
SHA-256: f4eac6df18e1da927441480a948c49041b9b6d2fb5f4c1457d4e8c8c37a861ea
font_01_sfnt_off0000f29f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF29F 18016 bytes
SHA-256: f9a0bd536dc1ee7a531b97fa3046b7df55f467997b05d2b36a4a19d2da838a70
font_02_sfnt_off000120ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1