Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4bad97aa0a2a1dd…

MALICIOUS

PDF

94.4 KB Created: 2021-09-08 20:58:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: cf00913691857a5577b08086dad49b2d SHA-1: 089737a3c53037fcc512efb3ef72edb262a366ac SHA-256: d4bad97aa0a2a1dd9708a823d9e334020fc7bf5cabb710961c9b2a50832add75
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. Heuristics indicate this is a link farm, likely used for SEO manipulation or to redirect users to malicious sites. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://woori-tour.kr/FileData/ckfinder/files/20210906_30EE0658AA6BAF03.pdf In PDF document text
    • http://style4.allwebeasy.com/userfiles/files/xezedoposavulufiwoniv.pdfIn PDF document text
    • http://nagymester.com/userfiles/file/82930977588.pdfIn PDF document text
    • http://netwindowvn.com/uploads/userfiles/file/58042902540.pdfIn PDF document text
    • http://thevale.us/userimages/gipufogol.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/22221282959.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/161365c6b41bc2---51130862049.pdfIn PDF document text
    • http://yalcinsezer.com/upload/ckfinder/files/kexogufotavapax.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/varadufixivi.pdfIn PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210909_AEFD99FCBE98705F.pdfIn PDF document text
    • http://k2plusinterior.com/userfiles/bigesusurajenobe.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/161315921cd5e4---150165361.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/zekirixobifitojarajabera.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/gijenixexufirit.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16134b7f8e5f0e---jesupowemib.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/51926594545.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/paviwepimowokewozejuk.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/17673530800.pdfIn PDF document text
    • http://i-p-p-c.com/ckfinder/userfiles/files/fuvemugolosorabomagepup.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/hpigv6dr873ig1jb80ip3q4r72/99840709130.pdfIn PDF document text
    • http://gidromall.ru/img/uploads/file/rebore.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/46562936514.pdfIn PDF document text
    • https://consultemergingmarkets.cubsindia.com/files/bipuganaditokowabomezoli.pdfIn PDF document text
    • http://notar-frings.de/userfiles/file/gaxuzidut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=meeting+at+night+critical+analysis+pdfPDF link annotation
    • https://b2cdemo.tickets.com/content/files/doxexaguradeg.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_off00010989.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10989 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001219b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1219B 19084 bytes
SHA-256: cf3245402bc3c8231d2de331c2a47f636c6ba5d3407d95aebf458cdde2f2551a
font_02_sfnt_off00015310.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15310 10888 bytes
SHA-256: 445b6a24ea7a3792ba5bd1bf835c5d4250c7220612bf71927b1be887c846cf92