Malicious PDF — malware analysis report

Static analysis result for SHA-256 462e3ea1c90cb2a8…

MALICIOUS

PDF

86.5 KB Created: 2021-09-01 04:27:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1e4838d24547b3499432d30a226b9e56 SHA-1: 5e42a8b9d6abbd286e3cb8a78538c6cbcbc244dc SHA-256: 462e3ea1c90cb2a87875293177b95cc4e2392d10626a2455c5f4747a17c28e07
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous external PDF files, many hosted on compromised CMS upload directories. The ML classifier strongly indicated maliciousness. While no scripts were extracted, the structure suggests the document is designed to lure users to these external resources, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • 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://royalwedding.jp/images/blog//file/89089505131.pdf In PDF document text
    • https://bostoncake888.com/UserFiles/files/wizajezege.pdfIn PDF document text
    • https://xeroxexpres.cz/userfiles/file/jewewewadunokovijag.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/160827d7c4be60---11081615637.pdfIn PDF document text
    • http://limoride.net/gallery/file/96778994612.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1606f483337069---rifofot.pdfIn PDF document text
    • http://www.w.radeton.cz/ckfinder/userfiles/files/88778844006.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f4aa11ebd---penorizipokujepudubawaxaz.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16100e3d763cd6---11503181189.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/71652019941.pdfIn PDF document text
    • https://cargoservice.pl/cargoservice/userfiles/file/nidebidabi.pdfIn PDF document text
    • http://gildiamasterov.ru/userfiles/file/dugin.pdfIn PDF document text
    • https://akemi.ro/hirek/file/47300065988.pdfIn PDF document text
    • https://tomas-music.com/contents//files/posabozavapure.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/nirefexepi.pdfIn PDF document text
    • https://wecareu.net/ckfinder/userfiles/files/vovotiv.pdfIn PDF document text
    • http://farmaciafici.com/userfiles/files/82044567827.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611a8b5b4005c---tigom.pdfIn PDF document text
    • http://av-jet.ru/userfiles/file/74686010225.pdfIn PDF document text
    • https://tannhatviet.vn/upload/files/73411703369.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/516d4c14ecf7e2fad2846d3ac3e6299f/tepiser.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=8085+instruction+set+with+examples+pptPDF 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_off0000ea09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA09 17752 bytes
SHA-256: 3a9809ab6b8a1cc6588f7abbbd40d611c16054fb3110011878f9441d5d040942
font_01_sfnt_off00011873.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11873 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001308a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1308A 11292 bytes
SHA-256: 064c25ff7969eae93c600f8cf0f087c33c0ea1ecc8d46baf76d0818f8daed719