Malicious PDF — malware analysis report

Static analysis result for SHA-256 6477b0a9c82fa271…

MALICIOUS

PDF

86.1 KB Created: 2021-07-19 21:56:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0c97fdc7a0e01c0922c699cce0ed3ba7 SHA-1: 437f3c3b5da9e90922b19cb304465ca633a784b9 SHA-256: 6477b0a9c82fa2718a44bce2f6b365bcbaa8a8ea71c98b2ef309761bb7e62748
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are associated with compromised CMS uploads or disposable hosting. The document body is heavily obfuscated, preventing analysis of its direct content, but the overall structure suggests an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://ligneus.hu/upload/file/figufijupekagir.pdf In PDF document text
    • http://tremonttemplemacon.com/clients/862779/File/29384131338.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/pisipu.pdfIn PDF document text
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/65028067346.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af90f27e52b---47507225473.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160794f3d1d0b3---53704944427.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/24c55b89e4d4cd9c545dcd2ff0ffd367/72551071690.pdfIn PDF document text
    • http://wamer.org/userfiles/file/jelajefutida.pdfIn PDF document text
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/51926417535.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/fe6ce33aaedf2b9a5913d028902412cc/71541045654.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/b3068bc191b1f93445bcd22230ed7cea/93939046151.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b30acf9de1a---31659735653.pdfIn PDF document text
    • http://seashoresilverlabradors.com/clients/4/48/482fd9669fb3260065120a60ccac5e48/File/55851495430.pdfIn PDF document text
    • http://csc-021.com/userfiles/file/20210629134737_911l4z.pdfIn PDF document text
    • http://myboydfamily.com/clients/7/7f/7f513a2250c12de81a70a6735749c289/File/40042081716.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/jovidifasapajavolu.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/1f1c6dfa82f45b26f8e23714bfdea8a5/dovexolumuvurupazume.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=what+is+my+mums+cousins+to+mePDF 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_off0000eb39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB39 18644 bytes
SHA-256: f983297ad74793f564dd6228e20979495de3da82f349c3f3341d4b58995921ea
font_01_sfnt_off00011bbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BBF 10556 bytes
SHA-256: 63dc2bcba3723ff833feea7ea4c3dc3554a7d0ac98cbcf6e8c24f02d837440bf
font_02_sfnt_off000133bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1