Malicious PDF — malware analysis report

Static analysis result for SHA-256 6dfb3fe1cb168de4…

MALICIOUS

PDF

95.2 KB Created: 2021-09-17 06:37:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ab16418ad1a1eb517f0c56da59e7dce8 SHA-1: 452c5823a4a8e4d6a3722b196bdb7ac7e00dc44f SHA-256: 6dfb3fe1cb168de42593e3a3e9e552673bde221ebe8e74904997475d6a52b08f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to domains associated with link farms and compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and link farm heuristics points towards a tactic of directing users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://zhxndl.com/uploadfiles/files/jukunogaloruroxu.pdf In PDF document text
    • http://rapet.hu/files/852110896.pdfIn PDF document text
    • http://kingsap.com/file_media/file_image/file/41284223885.pdfIn PDF document text
    • http://22vek-omsk.ru/fck_editor_files/files/memuwaretibobexejetefav.pdfIn PDF document text
    • https://interconformity.ro/images/file/todepu.pdfIn PDF document text
    • http://caycanh.vn/images/fck/file/58595078993.pdfIn PDF document text
    • http://ecolservizinettuno.com/userfiles/files/tarelawimufoxudulepukufox.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/mco1up2pqt89678h3ut0u3ia9n/904030897.pdfIn PDF document text
    • http://phongthuydotho.vn/upload/files/goforox.pdfIn PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/88744463291.pdfIn PDF document text
    • http://meyergarden.com/ckfinder/userfiles/files/44416612823.pdfIn PDF document text
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/lupemokufosaxena.pdfIn PDF document text
    • http://slenderclub.cz/ckfinder/userfiles/files/67652594300.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210908115404.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/vevewesilitonemap.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/6c53e1cf1732f564244d668f5db6318a/raborixasujarirogu.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141a8594906b---folonetawovojabenedumolav.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/37900329624.pdfIn PDF document text
    • http://commandhousecreations.com/uploads/files/fisonegifeduxep.pdfIn PDF document text
    • http://viprealestatebrokers.com/userfiles/files/26085187538.pdfIn PDF document text
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/12618850021.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/pugavelela.pdfIn PDF document text
    • http://schokoladenbrunnen.de/idata/taledavur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=age+of+empires+1997+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_off000111b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000129c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129C8 17364 bytes
SHA-256: e4998c837e873a17d0c83a42360a210e0ccd970d5cf75fc23de38fb478d35ef0
font_02_sfnt_off000156be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156BE 10796 bytes
SHA-256: 824f37fee7a59d33370b834a9816bdcae70dde7f1254b1a84ecd8523160b9e25