Malicious PDF — malware analysis report

Static analysis result for SHA-256 3809356cff51e01e…

MALICIOUS

PDF

93.5 KB Created: 2021-09-04 07:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 801b88f8604f4a21439dc292f2263c72 SHA-1: a755de99a6b4883f72f2e4653bbf3695cecb682a SHA-256: 3809356cff51e01ee902b31c8e7640a1e86364ed596c06a24a0651ddee27ec04
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicates maliciousness, and the heuristic firings suggest this PDF is a link farm designed to direct users to potentially malicious content or further compromise. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/lgtt2lp72smsr6pan6c6rhqc15/3574263023.pdf In PDF document text
    • http://stasta.com/userfiles/file/luxob.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be0eb925f69---20935810476.pdfIn PDF document text
    • https://elpmarketing.ca/wp-content/plugins/super-forms/uploads/php/files/409701d41d0774488dbb41cb07de1d20/46450460347.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c3d55d2124b---bejofupazisawezidefexali.pdfIn PDF document text
    • https://xuanhongkhang.com/upload/files/37418681355.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/bumewan.pdfIn PDF document text
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/f0953537f8766c98e97c67065ce389d9/wugomatu.pdfIn PDF document text
    • https://ghnservizi.com/file/35809572602.pdfIn PDF document text
    • http://opalsolar.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608720ac876aa---sebemuferowojuri.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/86020789897.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/ac4e9753b01a8913186b074e35c8d819/mukawojifoxoderexavodu.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/52680793306.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8b4a037264---16919061438.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607892ef49708---56169365926.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c082ad8a256---goruwozumuzulari.pdfIn PDF document text
    • https://adikkeempat.com/contents//files/85843536988.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202105151115106595.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/27713694777.pdfIn PDF document text
    • http://cascad-trans.ru/files/lixuneramezotazi.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2493d56220---folirodutup.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/8d5b4a72d2d3a73da25fcd44e9ad7cea/lojozodemu.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/d4b441c80afd7a6c384daaa3f1de969f/6334351564.pdfIn PDF document text
    • http://hoangle.vn/uploads/userfiles/file/gagilizitekipifetugu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=surreptitious+entry+and+restraint+defeat+manualPDF 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_off000105fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105FD 18676 bytes
SHA-256: 57b025e838f21e68e48909089bad54c92584dd1d5abcf2e2d75975fecb47cebc
font_01_sfnt_off000136c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136C2 10948 bytes
SHA-256: 18324e97f2302aa3bf753df57e0a9d3a0f421266f32e1ee34d36477441fd4610
font_02_sfnt_off00015022.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15022 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1