Malicious PDF — malware analysis report

Static analysis result for SHA-256 2610d21902caf679…

MALICIOUS

PDF

81.8 KB Created: 2021-09-07 00:18:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 59fa452ec51db83ae4badfc9067af451 SHA-1: 4a8d7acba8ddeb838427c3a18d368eef9bf2018d SHA-256: 2610d21902caf679c2bb2f058edc851e49fea0ee14dfa3f06eb42fe07e9a3400
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of a link farm designed to direct users to external, potentially malicious, websites. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://oniceh.ru/uplcv?utm_term=glas+znanja+knjiga+pdf PDF link annotation
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/dc028b54ad7b71cf9e19a6e93b7d214e/fibogemi.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/efea21efe646fd9e753c59df39469e0a/87692710310.pdfIn PDF document text
    • https://eghamatyab.com/basefile/bainbookcom/files/63390041811.pdfIn PDF document text
    • http://atek-ent.com/upload/file/rekokiwanewupugometerufi.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/766842ef7da9a8cde5b4e5c9c027b847/98643413665.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1608516e5468ea---wigulukakawi.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/usm6adgvo8hvuccj2nn4g8k0i6/38285678870.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/73872460810.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/283646bc8d919a51d0846fd4487919eb/82154706828.pdfIn PDF document text
    • https://machinex-machines.com/UserFiles/File/tejajumedibejolupen.pdfIn PDF document text
    • http://creptiles.dk/userfiles/file/46200643107.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/guwupikogunimetab.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4a6c230666---gotaxozujedojetu.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/28588598091.pdfIn PDF document text
    • http://www.dramayaramendes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160704f72e12bd---timaxamepaz.pdfIn PDF document text
    • http://hengtaixin.com/HangShun/ckfinder/userfiles/files/wedivemunisamiluv.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/tm5l0kb08m5usbs216c0fgf0ii/54033976192.pdfIn PDF document text
    • http://www.santabriganti.org/admin/ckfinder/userfiles/files/64432580700.pdfIn PDF document text
    • http://veivel.com/userfiles/file/zunoza.pdfIn PDF document text
    • http://droneducational.com/admin/userfiles/file/69451582049.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/rosemuzejegudejoju.pdfIn PDF document text
    • https://sayurhijau.com/contents//files/pokazog.pdfIn PDF document text
    • http://activesolutionelectric.com/images/file/vatawaxoxudujenetidavaj.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/pj7uakm2mt2cpn5096vlj7uktl/19968367363.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_off0000de00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE00 17408 bytes
SHA-256: 2c13de6608358b284a1c86616b4c8c7b5db0ee76aceb65f20eefb4b22b3d8ea1
font_01_sfnt_off000109dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DC 10544 bytes
SHA-256: 3cb31af327d5ad1f98f9b80f0a4cebc89b201da6144a3bc336f836bc87a3a54d
font_02_sfnt_off000121c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1