Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a5610c78a25f08e…

MALICIOUS

PDF

71.7 KB Created: 2021-09-04 16:47:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 04db11050e2efdc0e76729d6c62c0f2b SHA-1: 7a2007e63d607b740853edb300f9aeaa3085f5db SHA-256: 9a5610c78a25f08e1355c44777fc60640672189c345bf0611ca8088756580a7d
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious. It contains numerous links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to direct users to external, potentially malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://h-st.nl/bestanden/files/45716109054.pdf In PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16075c6e8856fa---76871059001.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/f0e498ddc9d2bbfffb6a0143bf1d90ca/soxejimi.pdfIn PDF document text
    • http://aylincinarli.com/fckfiles/file/46707862884.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/fhghv7obt826tigavp7kuo9504/61999957749.pdfIn PDF document text
    • http://qhchemicalsfeed.com/upload/files/12434540317.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/siloxidutotujemobex.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/212a7c76ebac1a0f313d4206b740a500/9111243725.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607766ec28afc---26597534629.pdfIn PDF document text
    • http://natalieshuff.com/uploads/file/waxenuxulopomobusit.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/kimasusagobuwepovele.pdfIn PDF document text
    • https://atphp.ch/userfiles/file/41701398100.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/c83ce4e12c72a6bf25348b2f6e1009e2/7535062395.pdfIn PDF document text
    • http://www.huescalamagiaenfotos.com/userfiles/files/58416181348.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/0f1afb8ec9ad66c55e6e224734461a06/41612816117.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/8548805631.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/e7ae269b9fdc5560d3d6a133c0cb5fb9/98505734645.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160906e941d63b---6408095517.pdfIn PDF document text
    • http://wecans.net/_UploadFile/Images/file/25280787668.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/0ff9e2302cada68bc317433b41b182b0/29111428675.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/96805610673.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611162a8969cc---48911894848.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/nqp46siuc079b0evq23126a1hc/sitobuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=un+peacemaking+pdfPDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/ccb9d574f52dc7ee5bf3d2789283ffef/51099996375.pdfIn PDF document text
    • 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_off0000b900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB900 10532 bytes
SHA-256: 6952ea7072f9388a4f0546fb4b7fea1c5e42d4cc3542c12cf781ed01e819115e
font_01_sfnt_off0000d0b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0B7 15804 bytes
SHA-256: d4df8fcef50054a16a7d882a2bd6d7cb4b9f254bea7dbc281a6b1ee4d0e27e82
font_02_sfnt_off0000f8f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1