Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea5ef76007fdee2e…

MALICIOUS

PDF

77.1 KB Created: 2021-09-21 02:08:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fd27f89721771e1631d0c34069920ce6 SHA-1: d875858fd55c4255572021d631973fe0b1d56991 SHA-256: ea5ef76007fdee2ec54ddd3be172e36d44370cf6284a6e59b3d22eb9856edc62
96 Risk Score

Malware Insights

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

The PDF contains numerous links to external PDF files, many hosted on domains flagged as potentially compromised or disposable. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to manipulate search engine results or distribute further malicious content. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://yptea.com/data/fckeditor/files/33532777912.pdf In PDF document text
    • http://drivescuolaguida.it/userfiles/files/suwowipiwutuxoxafubizuver.pdfIn PDF document text
    • http://amghanoi.com/images/ckeditor/files/gunewide.pdfIn PDF document text
    • http://boldogelet.hu/media/88490248445.pdfIn PDF document text
    • http://uniradioweb.info/userfiles/file/37491953651.pdfIn PDF document text
    • http://klaaswester.nl/img/file/48503737307.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135e5ce52d14---32155879435.pdfIn PDF document text
    • http://laguna.piyawatgroup.com/images/files/9418833942.pdfIn PDF document text
    • https://takitech.hu/userfiles/file/97981064406.pdfIn PDF document text
    • http://print-resource.co.uk/ckfinder/userfiles/files/vopamug.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/45001755565.pdfIn PDF document text
    • https://apra.pl/files/file/88821812266.pdfIn PDF document text
    • http://vincitydata.com/uploads/ckfinder/files/79361906125.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/79130389667.pdfIn PDF document text
    • https://bangvetthuong.com/luutru/files/jonanotu.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16136a9731e58a---78772000891.pdfIn PDF document text
    • https://zlataraburmevuckovic.com/files/71183721949.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/c665173213f91b1dbd7685c3b8a7e168/puluremepozabepuxoratub.pdfIn PDF document text
    • http://dentalweek.eu/userfiles/files/9726504013.pdfIn PDF document text
    • http://elitvorota.ru/f/file/topamebetul.pdfIn PDF document text
    • http://landpas.pl/upload/file/wipojelotivudexavi.pdfIn PDF document text
    • http://yogo110.com/userfiles/file/94515007608.pdfIn PDF document text
    • http://latiendasegura.com/contable_prueba/userfiles/file/48680430551.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=cashflow+quadrant+audiobook+free+downloadPDF 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_off0000c842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC842 11048 bytes
SHA-256: 6c6401900b84dc6c7d680377dee6f91eaa5467e821c9cb0394ec98c544690130
font_01_sfnt_off0000e1c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9D8 17204 bytes
SHA-256: 8467ca5d8c66c9c4593928c8a792df0746585b56cbc0ea014411f6a0f5fceae0