Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfbcf7cc470f05cb…

MALICIOUS

PDF

87.4 KB Created: 2021-09-04 10:32:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f7b11f0b91d98e737e0c676ec8336ce3 SHA-1: 88a5eb31446928f39b1ef7ef580a4fc1cef79903 SHA-256: cfbcf7cc470f05cb42ec344aa0bca38c3ac4528772509dd387413d29fc9b3bc1
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, indicating a link farm designed to lure users to external content. ClamAV and ML classifiers strongly indicate malicious intent, likely phishing or malware distribution. The presence of a link farm and compromised hosting suggests an attempt to obscure the true destination and leverage potentially trusted domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a07f2590adc---61571468014.pdf In PDF document text
    • https://daiichitravel.com/uploads/news_file/31907281750.pdfIn PDF document text
    • http://blissrenewbeauty.com/newerac2c/userfiles/file/37157657169.pdfIn PDF document text
    • https://hyundainhapkhau.vn/upload/files/88327802774.pdfIn PDF document text
    • http://omni-links.com/94214688154.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/paturolesezezerof.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/jegemexegugetukidororuko.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/9c12d1f36262b2d3fe8461bb00bb0c5a/78927118256.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087bde9b3d50---mefij.pdfIn PDF document text
    • https://kurtoglumob.com/upload/file/7929620645.pdfIn PDF document text
    • http://investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/rutubob.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/7549546364.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/daziravimelava.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/dosuwetoxavuruxosel.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/12438617012.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/41796904013.pdfIn PDF document text
    • http://naphogacomposite.com/upload/files/xinofanugefu.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608750c12342b---gexelawuzan.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1611f6ebc7c43b---xibarejigesonazavarutagod.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/b8e9411d2d04a35f5ad63ce4ecfd1834/55804928731.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/2e5e5ab454d7affcc6a693e0c644d295/14961568711.pdfIn PDF document text
    • https://hoalavender.net/upload/files/33981054620.pdfIn PDF document text
    • https://valve-toho.com/userfiles/file/74834327878.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608e33123e2d3---zativuzofewanubu.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609b49d41347c---98309763352.pdfIn PDF document text
    • http://dgjst.com/upfile/file/51045143165.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=assam+tet+exam+syllabus+2019+pdfPDF 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_off0000ee46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE46 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010658.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10658 18172 bytes
SHA-256: ebcf23e4d29724e01dd4eca9fbb81c05b14cfba64a3583a1c047d1dae07dc73f
font_02_sfnt_off00013553.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13553 11144 bytes
SHA-256: d72f435044322663c29be27b6df56c5d7946d390873ea3dca5c7366b64e593e5