Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3f438c9e08ee7b3…

MALICIOUS

PDF

89.2 KB Created: 2021-07-02 09:42:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: baabc55a44d96c0461abe824e7aab2ae SHA-1: cc7cc647add562ae775bd84e00b21043ba3e72bd SHA-256: c3f438c9e08ee7b3eae62f9edb7107c89504436e89e3a212f808cfaa0a991338
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicates maliciousness. While no scripts were directly extracted, the structure and embedded links suggest this PDF is part of a link farm designed to distribute further malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://studio-september.com/wp-content/plugins/super-forms/uploads/php/files/3a3caef0ca888638d47a810bcbff084c/favoxuxikadusodisiwusef.pdf In PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/c75405ac9aeaccda1609cfdd4b3b6dd0/59263028906.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/44888848242.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/xisogamomeda.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/uugngt4alfptstc6fh5vhlflcu/mekolijosifawajapa.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2ec459856---420041664.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/wudilogowix.pdfIn PDF document text
    • http://abpaluso.com/upload/file/finaruvar.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081404ad121a---77453113911.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/20454195327.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/a868a1c6f45eb46fe3a0ea08c5cdb6bd/fejenadidi.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8a159de6d4---32441555858.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a086fb35e6f---77956282944.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/d6488422386ab2284762a02d0fd14399/dowewojim.pdfIn PDF document text
    • http://medob.org/SITE/files/editor/file/nokuxukeguzufepu.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/667a182a41bc92717102057b0b9441d0/rakudu.pdfIn PDF document text
    • http://beiwendq.com//data/attachment/file/6885483370.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/sagaxewexoretovuraladijev.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/e57d81c25d5b30e39fd7ab815b03e406/35927474862.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/ab7e003feef5745393358a2b047c3ab9/10317608458.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d55fc8bfa47---23532026238.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a62857d97f---mabopokikoxodes.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/1lem3h0t1pugllpeqr9rpghbr4/97492543743.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=puffy+and+painful+eyelidPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/6efd6e5c47c83a1ea748cadd564c4f35/zupekoxodatupigujuloxo.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_off0000fd12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD12 10220 bytes
SHA-256: 8653b22207f28996e1bca6a9892209ae99a34e0de2f8a4c9f22064b84eebbdc9
font_01_sfnt_off00011414.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11414 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C26 16724 bytes
SHA-256: 61208c396cc8bda07de04fba5ba6d68bfa9d1491e276c4042d19d0d85a2e6e9f