Malicious PDF — malware analysis report

Static analysis result for SHA-256 20cd1bfaf1a091ab…

MALICIOUS

PDF

74.3 KB Created: 2021-09-14 09:44:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b5f56b1c16a73860aaa2cca819f6649d SHA-1: e66e2bebbe6f84891076b86c588c84f773473852 SHA-256: 20cd1bfaf1a091ab9981247cadd573bae16ce2329241446a9fa44b75b9c7b4df
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous distinct hosts, many of which are hosted on compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns suggest a lure to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kenhquangcao.vn/uploads/files/gepiledokopudorifeziguz.pdf
    • https://hinaweb.com/upload/file/52655824667.pdf
    • http://np-laser.com/upload_fck/file/2021-9-9/20210909015419699453.pdf
    • https://regiefranchet.fr/userfiles/files/48654334094.pdf
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1613383d8e873b---nejigozuranuruzuju.pdf
    • http://evpltravel.com/xv_image/file/58920504180.pdf
    • http://hzbmsj.com/images/upload/File/befemo.pdf
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/pixodaboduwokumenarawur.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/uh7v7jt6rnbjuoqe3a6iejdqe6/8803815248.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613f7a398a29d---kosimipirixig.pdf
    • http://www.pibmg.com.br/ckfinder/userfiles/files/files/87491630844.pdf
    • http://www.alexgis.com/siteuploads/editorimg/file/telukunene.pdf
    • https://tramtron.vn/uploads/files/files/28603023497.pdf
    • http://chongthamphucthang.com/images/news/files/587177082.pdf
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1523e5eb4---mapogituzowato.pdf
    • http://files.ibiza-ferien.de/file/37875431905.pdf
    • http://cachnhietwin.com/luutru/files/xobepoxuxojaz.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/6fb3756f31688cc0adef1b59163e833b/dozimezef.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613e6f086df07---ponozununota.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613afa50d850d---96192822733.pdf
    • http://maymaygiaydachidang.com/upload/files/xesewotasenoguwimatosigen.pdf
    • https://smartcrm.cloud/upload/files/60529545644.pdf
    • http://facilitymanagementassociates.com/survey/userfiles/files/59572178520.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=android+tv+remote+app+won+t+connect
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c150.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC150 16792 bytes
font_01_sfnt_off0000d962.bin
1c7a9b959f1e7215d2dd0670e5688546757b7ff219bb893f65119c1bfcfebf0d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD962 16308 bytes
font_02_sfnt_off00010350.bin
0184f119d776726b49d2a26b345a7f63cdd35d366cb14ee64f8f8a0683b57973
pdf-font-stream PDF embedded font (sfnt) at offset 0x10350 10596 bytes