Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee4ea052b46a520f…

MALICIOUS

PDF

75.9 KB Created: 2021-09-24 20:31:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2737101c4f28bf91812447f618300d02 SHA-1: b0db506f96bde690f2ee39edd6a560ea6dcb6eb8 SHA-256: ee4ea052b46a520f786a6363c2a5d3eef95fdad9fa2a841ee2b6c79ad915718c
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs that form a link farm. These links predominantly point to compromised WordPress upload directories and disposable hosting, suggesting an attempt to distribute further malicious content. The ML classifier strongly indicated maliciousness, supporting the observed link farm behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://die-elke.de/cms/elke_page_files/file/vatubewu.pdf In PDF document text
    • https://mar3ol.com/Files/files/60650906192.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/papuvaguxajusefiwi.pdfIn PDF document text
    • http://ambiance-cinema.fr/wp-content/plugins/super-forms/uploads/php/files/cf4a17bd15a74dfeedd6d02731d1b69a/3095964772.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/refipaliribukezemub.pdfIn PDF document text
    • https://egf.tw/test2/images/file/47219835226.pdfIn PDF document text
    • http://chinhsuasolieu.com/media/files/17701830806.pdfIn PDF document text
    • http://mishelik.ru/userfiles/file/nudetegotuboz.pdfIn PDF document text
    • http://ambiance-cinema.fr/wp-content/plugins/super-forms/uploads/php/files/c9a4bd1f34ccc7f2d7567029ed1927f4/radas.pdfIn PDF document text
    • http://ksiclubbiz.ksiclub.org/svnprojects/DHD/Source/images/files/15479054797.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614072974ab92---xewulil.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/s4km43pffu53jj2a8mdg5d214k/noxofinezufujenutiwijiko.pdfIn PDF document text
    • http://rsport.eu/yonexshop/static/file/47238289433.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/xemizopofawek.pdfIn PDF document text
    • http://aaronandanthony.com/userfiles/files/tegizibajapefanomimijobik.pdfIn PDF document text
    • https://pepinieramontana.ro/ckfinder/userfiles/files/90688197649.pdfIn PDF document text
    • http://peach2560.xyz/js/ckfinder/userfiles/files/32120582259.pdfIn PDF document text
    • https://erdemlerkoleji.com/resimler/files/rebevokatikadagejiwo.pdfIn PDF document text
    • http://nyitotthaz.hu/userfiles/files/dufidufi.pdfIn PDF document text
    • http://wx-test.com/upload/ckimg/files/202109180318007764.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614095919a4ef---gilusokarimuli.pdfIn PDF document text
    • http://change4best.ru/upload/file/rekiral.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=amor+y+respeto+pdfPDF 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_off0000c011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC011 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD823 18740 bytes
SHA-256: 1e8e8ac24634780e2ca9dd8f7deb4b05d4a7f2bc683e174455e64c3d1b7124d5
font_02_sfnt_off00010912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10912 10348 bytes
SHA-256: ddc15b55eb1300acbf71a83cbe810c66b1b0d72fae0c2cd06759f16f5af390d5