Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6eff8b07649d1e6…

MALICIOUS

PDF

85.7 KB Created: 2021-09-18 10:46:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 75dc23c42bba91b2e5d96227048cf3dc SHA-1: f14e0962ff392a7a7498ba16a55fb051c04560f3 SHA-256: f6eff8b07649d1e648b9e67576ef0487b9acd5bab6e1a92d01e22163b47ac408
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to other PDF documents, many hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the structure and embedded URLs suggest a malicious document intended to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://haisanquangninh.org/data/dulieu/files/winifakapujudetugofufidov.pdf In PDF document text
    • http://beiks.info/public/file/bapojo.pdfIn PDF document text
    • https://mmrh.myagenda.cz/pictures/editor/files/zanunosilowulefalo.pdfIn PDF document text
    • http://dxline.eu/userfiles/file/20582272501.pdfIn PDF document text
    • http://taigesw.com/upload/files/kuxituxuzarinajowolo.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/4d46effc77f5f943ea87fc9157a99941/kogowedagesopegase.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/ilivtsbo91ju69mdvj3vthehbm/sitawame.pdfIn PDF document text
    • https://wangwangcamp.com/uploads/files/202109110748281243.pdfIn PDF document text
    • http://hsaltsj.com/uploads/files/51621543078.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/cq2q0tu4s0ijc1hmbtsnikl1v8/87982306599.pdfIn PDF document text
    • http://demo755.webbazaar.com/uploads/94151080766.pdfIn PDF document text
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/gazokuguremekujelik.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/40434569160.pdfIn PDF document text
    • https://dispecom.com/cms_dispecom/sgi_userfiles/userfiles/files/zodogeditetor.pdfIn PDF document text
    • http://cppzone.ru/users/blogs/file/8215541290.pdfIn PDF document text
    • http://3m18.com/images/editor/files/nokekarudusidixus.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/toponufukaj.pdfIn PDF document text
    • http://pressvaluation.net/FCKeditor/editor/filemanager/connectors/userfiles/file/dijakum.pdfIn PDF document text
    • http://pelejas.com/IMAGENS/CKFINDER/files/nokuxaxusaxirogip.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109140617167290.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d116e6255---1576846388.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/99020061817.pdfIn PDF document text
    • https://ms02bet.net/contents/files/69751508915.pdfIn PDF document text
    • https://www.abrasco.org.br/ckfinder/userfiles/files/64522019292.pdfIn PDF document text
    • http://abbeloosschinkels.be/userfiles/file/nawevamopoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=pc+convert+to+android+softwarePDF 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_off0000e941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE941 18320 bytes
SHA-256: a49b804bb3207a6a352af343ed373d8c20a6e4b61a6ad6d781367e7eb8e70360
font_01_sfnt_off000118b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118B7 10576 bytes
SHA-256: 0a25dc030ff8fc7fe2406a7cc0b24bc5396f808a6de5e9a9cd5605fb3481fd14
font_02_sfnt_off00013116.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13116 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1