Malicious PDF — malware analysis report

Static analysis result for SHA-256 61ce0a8b8a618501…

MALICIOUS

PDF

83.4 KB Created: 2021-07-26 08:20:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c13b3f31f5a806426707de885d2fae6c SHA-1: 6244972891b255013c5a8b274de3cf46fae721dc SHA-256: 61ce0a8b8a618501891af3a8807a8b6dc40e5014d5fc090f64f5c32b0288221d
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classification and ClamAV detection. It contains a link farm pointing to compromised WordPress sites and other domains, suggesting an attempt to distribute malware or conduct phishing. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for human readability but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/6pg0bsk79hcha0nko17v1j8rbp/52046854837.pdf In PDF document text
    • http://hanhthien.net/uploads/file/rurumijes.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/2s00k34qagifom3cd475jg7j2b/64195904317.pdfIn PDF document text
    • http://americusfelderfamily.com/clients/0/0c/0c5e5e27a4da9db51eb23c24aa0fa274/File/43661499864.pdfIn PDF document text
    • http://fvv-hohenfelde.de/sites/default/files/files/vopow.pdfIn PDF document text
    • http://studiovalecchi.it/userfiles/files/zadikod.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/cp1jq21cqnqrk42l3265q06d2a/rugesaj.pdfIn PDF document text
    • http://nesthomes.in/userfiles/file/63616018408.pdfIn PDF document text
    • https://artbynela.com/uploads/file/vozutadezunaxe.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/seutfl4865nsq5qkso249mdvea/beninopixuwexag.pdfIn PDF document text
    • https://okinawa4d.com/contents//files/leroxoku.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16072e22155c30---40864311195.pdfIn PDF document text
    • http://goraku-sangyo.com/userfiles/file/jojikezaliletaf.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///fagoxa.pdfIn PDF document text
    • https://forthepeoplegov.com/userfiles/file/78062074878.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16082671bee281---zoxefalete.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cedb388ae0---tojeb.pdfIn PDF document text
    • https://eberli-medical-supply.ch/upload/file/14604943182.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/44fee224e60404f618f1072fbdd4818f/73817801825.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=exercices+sur+les+antonymes+cm2+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_off0000df4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4E 11200 bytes
SHA-256: caa67a9cc815f01dd2e02a5b79346b01ba456ad614019461e3aa1f035763fe36
font_01_sfnt_off0000f99f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF99F 17884 bytes
SHA-256: 359c2098b87716ddbdfac086162c43c2d1c2917bd5b426b05ae8ec5e903769ea
font_02_sfnt_off00012672.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12672 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1