Malicious PDF — malware analysis report

Static analysis result for SHA-256 1873b9775684183e…

MALICIOUS

PDF

72.5 KB Created: 2021-06-24 23:25:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: f8391b65d5fdb9a91eb24a9e143c8b94 SHA-1: 9919d2f3e3890752284d5d2b08b02cef1c4c5857 SHA-256: 1873b9775684183ebbae93a847e3f03688c17812014d79a07bb2d24a517cbcb4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://michelesherrinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/mukesesuv.pdf In PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160b87a921d9e5---katavukemubanunakoj.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/nvdraoh57lt4qvdon6rbct4440/wakekevazejejiw.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/c9c560260cfb0b7ca7462d9f8d4f7f79/61796344254.pdfIn PDF document text
    • http://luatsuphutho.com/upload/ck/files/bezobirunano.pdfIn PDF document text
    • http://www.celso.org/download/kigopikabenesaw.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/b3f5eb62136ea692ad025d29e4435830/23927186652.pdfIn PDF document text
    • http://ya-ke.cn/admin/upload/kapawuwidaniroguzofuniwi.pdfIn PDF document text
    • http://pahsclassof2005.com/clients/d/d6/d61c4c031b0f3af13d3e88110ef3a3e1/File/pemumodosovoxup.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/794mbmqbo9l07akjpcf31uhqk8/13366816212.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/lekogowovot.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079290cb6b79---18555803561.pdfIn PDF document text
    • https://najlepsze-w-polsce.pl/uploads/2492415656.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160ba25abd93d8---bigevozobo.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607387224169d---nedaripudavivolu.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/bosupifebax.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/07a8b57859244b267930ce6af9b449c1/90451425288.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b4e57c9cfe4---pubuvudedunulana.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=chess+free+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e299.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE299 4792 bytes
SHA-256: 5f3701018c89675a877f130f5666e41721be63695f86f21e3cf80cf1673dbd02
font_01_sfnt_off0000f2de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2DE 10044 bytes
SHA-256: 6c852cfdeee9e4bd2739fb9d79364ea80208d6799a42714599aff1b280148d8d